PGP 6.5i and OE5

I configured a client for OE5 and PGP6.5i. I've done this before without incident. Everything works fine except ... that when I create a new mail message I do NOT get the PGP Encrypt and PGP Sign buttons. Stranger still, each time I create a new message an additional toolbar separator line appears at the end of the toolbar icons. If I go to customize the toolbar and remove all those stray separators, the Encrypt and Sign icons appear! The next time I go to create a message, however, the separators start accumulating again, and the buttons no longer appear (back to where I started). The PGP functionality works, however, but this strange situation makes me nervous.

I have uninstalled PGP and reinstalled it - no change.