Why am I getting an 'Invalid Server Certificate' error when retrieving email even though I have the 'Verify Certificate' setting disabled?
This seems like an issue that has been reported to the android development team. I am not sure if it is specific to the droid x, but even the work item relates to the droid x. If that is the case, I don't know if that is technically an android issue, but a MotoBLUR issue, as the Droid X runs the MotoBLUR version of android.

Also, Yes, that is what "Never use secure password" means.