College Linux, you say? Hmm....
As far as I know, the installpkg tool is a Slackware-specific package tool, not to mention your version is an older one that doesn't read the file name correctly.
Try mv dropline-installer-2.0.5-i386-3d1.tgz dropline_installer-2.0.5-i386-1.tgz If that doesn't work, it may be a very old version of installpkg that reads the old format, in which case the version, architecture, and build step numbers get dropped completely (again, not to mention reverting back to 8 character format), and the filename would then be: dropline.tgz
That may clear things up. Hope that helps.