Magicfilter depends on being able to tell what kind of file it is. I think the file has to begin with "%!PS-Adobe-" for it to be detected as PostScript. Is that the case? Try sending it small PostScript files and see if it gets it right.
If I still remember PostScript this should work for a test. Bruce %!PS-Adobe-1.0 save /Helvetica-Bold findfont 18 scalefont (Hello World!) show showpage restore -- TO UNSUBSCRIBE FROM THIS MAILING LIST: e-mail the word "unsubscribe" to [EMAIL PROTECTED] . Trouble? e-mail to [EMAIL PROTECTED] .