(1) I'm in src/usr.sbin/pkg_add. I type "vi pod/<tab>". ksh prints some completions for me:
athens:~/src/usr.sbin/pkg_add> vi pod/ CVS/ OpenBSD::PackingElement.pod ... (2) I type "Open<tab>". ksh completes a little more for me: athens:~/src/usr.sbin/pkg_add> vi pod/OpenBSD:: (3) I type <tab> again: athens:~/src/usr.sbin/pkg_add> vi pod/OpenBSD:: CVS/ obj/ pkg_check.8 ... oops! Now I'm looking at files in . again. (4) I type G to give it a hint. hitting tab shows no completions: athens:~/src/usr.sbin/pkg_add> vi pod/OpenBSD::G (5) Backspace and add some backslashes as so: athens:~/src/usr.sbin/pkg_add> vi pod/OpenBSD\:\:G Then I hit tab again: athens:~/src/usr.sbin/pkg_add> vi pod/OpenBSD::Getopt.pod tada! Now it works and the backslashes are gone again. If ksh is going to treat : as magic, then it needs to escape it when autocompleting. (step 2 above)