p = ','.join( params )
    cmd = "select %s from measures into outfile '/tmp/auto.plt'"
    curs.execute( cmd, p )

outputs to /tmp/auto.plt:
scaling,redness,timestamp
scaling,redness,timestamp


whereas if i do 
curs.execute( "select scaling,redness,timestamp from measures into outfile '/tmp/auto.plt'" )
/tmp/auto.plt: gives: (which is what i want)
3	1	2007-04-13 23:18:41
\N	1	2007-04-14 23:03:40

try:
 p = ','.join( params )
    cmd = "select %s from measures into outfile '/tmp/auto.plt'"%p
    curs.execute( cmd)