Index: src/server/adminmanager.cpp
===================================================================
--- src/server/adminmanager.cpp	(revision 5627)
+++ src/server/adminmanager.cpp	(working copy)
@@ -673,12 +673,14 @@
             }
             else
             {
+                if(words[3][0] == '+' || words[3][0] == '-')
+                    insert = true;
                 value = words.GetInt(3);
             }
         }
         else
         {
-            value = -2;
+            help = true;
         }
         return true;
     }
@@ -6650,9 +6652,9 @@
         }
     }
     // Not a copy, just proceed as normal
-    else if (data.skill.IsEmpty() || data.value == -2)
+    else if (data.skill.IsEmpty() || data.help)
     {
-        psserver->SendSystemError(me->clientnum, "Syntax: /setskill [target] [skill|'all'] [value|-1] | [target] copy [source]");
+        psserver->SendSystemError(me->clientnum, "Syntax: /setskill [target] [skill|'all'] [+-][value] | [target] copy [source]");
         return;
     }
 
@@ -6679,15 +6681,16 @@
         return;
     }
 
-    // use unsigned int since skills are never negative (this also takes care of overflows)
-    unsigned int value = data.value;
-    unsigned int max = MAX(MAX_SKILL, MAX_STAT);
+    // use signed int as we're accepting relative values
+    int value = data.value;
+    // use the minimum here to not award values bigger than possible by setting single skill
+    int max = MIN(MAX_SKILL, MAX_STAT);
     if (data.skill == "all")
     {
         // if the value is out of range, send an error
-        if (data.value != -1 && (value < 0 || value > max))
+        if (!data.insert && (value < 0 || value > max) || data.insert && (value < -max || value > max))
         {
-            psserver->SendSystemError(me->clientnum, "Valid values are between 0 and %u", max);
+            psserver->SendSystemError(me->clientnum, "Valid values are between 0 and %d", max);
             return;
         }
 
@@ -6696,9 +6699,7 @@
             psSkillInfo * skill = CacheManager::GetSingleton().GetSkillByID(i);
             if (skill == NULL) continue;
 
-            unsigned int old_value = pchar->Skills().GetSkillRank(skill->id).Current();
-
-            if(data.value == -1)
+            if(data.insert && data.value == 0)
             {
                 PSITEMSTATS_STAT stat = skillToStat(skill->id);
                 if (stat != PSITEMSTATS_STAT_NONE)
@@ -6707,32 +6708,49 @@
                     int base = pchar->Stats()[stat].Base();
                     int current = pchar->Stats()[stat].Current();
                     if (base == current)
-                        psserver->SendSystemInfo(me->clientnum, "Current '%s' of '%s' is %u", skill->name.GetDataSafe(), target->GetName(), base);
+                        psserver->SendSystemInfo(me->clientnum, "Current '%s' of '%s' is %d", skill->name.GetDataSafe(), target->GetName(), base);
                     else
-                        psserver->SendSystemInfo(me->clientnum, "Current '%s' of '%s' is %u (%u)", skill->name.GetDataSafe(), target->GetName(), base, current);
+                        psserver->SendSystemInfo(me->clientnum, "Current '%s' of '%s' is %d (%d)", skill->name.GetDataSafe(), target->GetName(), base, current);
                 } else {
                     int base = pchar->Skills().GetSkillRank(skill->id).Base();
                     int current = pchar->Skills().GetSkillRank(skill->id).Current();
                     if (base == current)
-                        psserver->SendSystemInfo(me->clientnum, "Current '%s' of '%s' is %u", skill->name.GetDataSafe(), target->GetName(), base);
+                        psserver->SendSystemInfo(me->clientnum, "Current '%s' of '%s' is %d", skill->name.GetDataSafe(), target->GetName(), base);
                     else
-                        psserver->SendSystemInfo(me->clientnum, "Current '%s' of '%s' is %u (%u)", skill->name.GetDataSafe(), target->GetName(), base, current);
+                        psserver->SendSystemInfo(me->clientnum, "Current '%s' of '%s' is %d (%d)", skill->name.GetDataSafe(), target->GetName(), base, current);
                 }
             }
             else
             {
-                pchar->SetSkillRank(skill->id, value);
-                psserver->SendSystemInfo(me->clientnum, "Changed '%s' of '%s' from %u to %u", skill->name.GetDataSafe(), target->GetName(), old_value,data.value);
+                int old_value = pchar->Skills().GetSkillRank(skill->id).Current();
+                int new_value;
+                if (data.insert)
+                {
+                    if (value > 0)
+                        new_value = old_value + value > max ? max : old_value + value;
+                    else
+                        new_value = old_value + value < 0 ? 0 : old_value + value;
+                }
+                else
+                {
+                    new_value = value;
+                }
+
+                pchar->SetSkillRank(skill->id, new_value);
+                psserver->SendSystemInfo(me->clientnum, "Changed '%s' of '%s' from %d to %d", skill->name.GetDataSafe(), target->GetName(), old_value, new_value);
             }
         }
+        
+        if (data.insert && data.value == 0)
+        	return;
 
-        if(data.value != -1)
-            return;
-
         if (target->GetClient() && target->GetClient() != client)
         {
             // Inform the other player.
-            psserver->SendSystemOK(target->GetClientID(), "All your skills were set to %d by a GM", data.value);
+            if (data.insert)
+                psserver->SendSystemOK(target->GetClientID(), "All your skills were adjusted by %d by a GM", value);
+            else
+                psserver->SendSystemOK(target->GetClientID(), "All your skills were set to %d by a GM", value);
         }
     }
     else if (data.skill == "copy")
@@ -6764,8 +6782,7 @@
             return;
         }
 
-        unsigned int old_value = pchar->Skills().GetSkillRank(skill->id).Current();
-        if (data.value == -1)
+        if (data.insert && data.value == 0)
         {
             PSITEMSTATS_STAT stat = skillToStat(skill->id);
             if (stat != PSITEMSTATS_STAT_NONE)
@@ -6774,37 +6791,44 @@
                 int base = pchar->Stats()[stat].Base();
                 int current = pchar->Stats()[stat].Current();
                 if (base == current)
-                    psserver->SendSystemInfo(me->clientnum, "Current '%s' of '%s' is %u", skill->name.GetDataSafe(), target->GetName(), base);
+                    psserver->SendSystemInfo(me->clientnum, "Current '%s' of '%s' is %d", skill->name.GetDataSafe(), target->GetName(), base);
                 else
-                    psserver->SendSystemInfo(me->clientnum, "Current '%s' of '%s' is %u (%u)", skill->name.GetDataSafe(), target->GetName(), base, current);
+                    psserver->SendSystemInfo(me->clientnum, "Current '%s' of '%s' is %d (%d)", skill->name.GetDataSafe(), target->GetName(), base, current);
             } else {
                 int base = pchar->Skills().GetSkillRank(skill->id).Base();
                 int current = pchar->Skills().GetSkillRank(skill->id).Current();
                 if (base == current)
-                    psserver->SendSystemInfo(me->clientnum, "Current '%s' of '%s' is %u", skill->name.GetDataSafe(), target->GetName(), base);
+                    psserver->SendSystemInfo(me->clientnum, "Current '%s' of '%s' is %d", skill->name.GetDataSafe(), target->GetName(), base);
                 else
-                    psserver->SendSystemInfo(me->clientnum, "Current '%s' of '%s' is %u (%u)", skill->name.GetDataSafe(), target->GetName(), base, current);
+                    psserver->SendSystemInfo(me->clientnum, "Current '%s' of '%s' is %d (%d)", skill->name.GetDataSafe(), target->GetName(), base, current);
             }
             return;
         }
-        else if (skill->category == PSSKILLS_CATEGORY_STATS && (value < 0 || value > MAX_STAT))
-        {
-            psserver->SendSystemError(me->clientnum, "Stat values are between 0 and %u", MAX_STAT);
-            return;
-        }
-        else if (skill->category != PSSKILLS_CATEGORY_STATS && (value < 0 || value > MAX_SKILL))
-        {
-            psserver->SendSystemError(me->clientnum, "Skill values are between 0 and %u", MAX_SKILL);
-            return;
-        }
 
-        pchar->SetSkillRank(skill->id, value);
-        psserver->SendSystemInfo(me->clientnum, "Changed '%s' of '%s' from %u to %u", skill->name.GetDataSafe(), target->GetName(), old_value,data.value);
+        int old_value = pchar->Skills().GetSkillRank(skill->id).Current();
+        int new_value;
+        if (data.insert)
+            new_value = old_value + value;
+        else
+            new_value = value;
 
+        if (skill->category == PSSKILLS_CATEGORY_STATS)
+            max = MAX_STAT;
+        else if (skill->category != PSSKILLS_CATEGORY_STATS)
+            max = MAX_SKILL;
+
+        if (new_value > max)
+            new_value = max;
+        else if (new_value < 0)
+            new_value = 0;
+
+        pchar->SetSkillRank(skill->id, new_value);
+        psserver->SendSystemInfo(me->clientnum, "Changed '%s' of '%s' from %d to %d", skill->name.GetDataSafe(), target->GetName(), old_value, new_value);
+
         if (target->GetClient() &&  target->GetClient() != client)
         {
             // Inform the other player.
-            psserver->SendSystemOK(target->GetClientID(), "Your '%s' level was set to %d by a GM", data.skill.GetDataSafe(), data.value);
+            psserver->SendSystemOK(target->GetClientID(), "Your '%s' level was set to %d by a GM", data.skill.GetDataSafe(), new_value);
         }
     }