centos 5.1:
15:37:05.553266 IP 74.201.XXX.XXX.45467 > ftp1.XXXX.com.ftp: S 3436638979:3436638979(0) win 5840 <mss 1460,sackOK,timestamp 141439407 0,nop,wscale 7>
15:37:05.581441 IP ftp1.XXXX.com.ftp > 74.201.XXX.XXX.45467: S 1085275456:1085275456(0) ack 3436638980 win 16384 <mss 1024,nop,wscale 0,nop,nop,timestamp 10452674 141439407>
15:37:05.581622 IP 74.201.XXX.XXX.45467 > ftp1.XXXX.com.ftp: . ack 1 win 46 <nop,nop,timestamp 141439414 10452674>

seven minutes later it repeats


Trustix 2.2:
15:46:48.921699 IP 74.201.XXX.XXX.45467 > ftp1.XXXX.com.ftp: F 1:1(0) ack 1 win 46 <nop,nop,timestamp 141585247 10452674>
15:46:49.146782 IP 74.201.XXX.XXX.45467 > ftp1.XXXX.com.ftp: F 1:1(0) ack 1 win 46 <nop,nop,timestamp 141585304 10452674>
15:46:49.602790 IP 74.201.XXX.XXX.45467 > ftp1.XXXX.com.ftp: F 1:1(0) ack 1 win 46 <nop,nop,timestamp 141585418 10452674>
15:46:50.514817 IP 74.201.XXX.XXX.45467 > ftp1.XXXX.com.ftp: F 1:1(0) ack 1 win 46 <nop,nop,timestamp 141585646 10452674>
15:46:52.338883 IP 74.201.XXX.XXX.45467 > ftp1.XXXX.com.ftp: F 1:1(0) ack 1 win 46 <nop,nop,timestamp 141586102 10452674>
15:46:55.986903 IP 74.201.XXX.XXX.45467 > ftp1.XXXX.com.ftp: F 1:1(0) ack 1 win 46 <nop,nop,timestamp 141587014 10452674>
15:46:57.541762 IP 74.201.XXX.XXX.54565 > ftp1.XXXX.com.ftp: S 3908408499:3908408499(0) win 5840 <mss 1460,sackOK,timestamp 56655139 0,nop,wscale 0>
15:46:57.569689 IP ftp1.XXXX.com.ftp > 74.201.XXX.XXX.54565: S 1255203292:1255203292(0) ack 3908408500 win 16384 <mss 1024,nop,wscale 0,nop,nop,timestamp 10453858 56655139>
15:46:57.569868 IP 74.201.XXX.XXX.54565 > ftp1.XXXX.com.ftp: . ack 1 win 5840 <nop,nop,timestamp 56655142 10453858>
15:46:57.599633 IP ftp1.XXXX.com.ftp > 74.201.XXX.XXX.54565: P 1:71(70) ack 1 win 16384 <nop,nop,timestamp 10453858 56655142>
15:46:57.599820 IP 74.201.XXX.XXX.54565 > ftp1.XXXX.com.ftp: . ack 71 win 5840 <nop,nop,timestamp 56655145 10453858>
15:47:01.089480 IP 74.201.XXX.XXX.54565 > ftp1.XXXX.com.ftp: F 1:1(0) ack 71 win 5840 <nop,nop,timestamp 56655494 10453858>
15:47:01.116652 IP ftp1.XXXX.com.ftp > 74.201.XXX.XXX.54565: . ack 2 win 16384 <nop,nop,timestamp 10453865 56655494>
15:47:01.117268 IP ftp1.XXXX.com.ftp > 74.201.XXX.XXX.54565: F 71:71(0) ack 2 win 16384 <nop,nop,timestamp 10453865 56655494>
15:47:01.117393 IP 74.201.XXX.XXX.54565 > ftp1.XXXX.com.ftp: . ack 72 win 5840 <nop,nop,timestamp 56655497 10453865>
15:47:03.283064 IP 74.201.XXX.XXX.45467 > ftp1.XXXX.com.ftp: F 1:1(0) ack 1 win 46 <nop,nop,timestamp 141588838 10452674>
15:47:17.875621 IP 74.201.XXX.XXX.45467 > ftp1.XXXX.com.ftp: F 1:1(0) ack 1 win 46 <nop,nop,timestamp 141592486 10452674>