Full Name blank on usersdisp.asp but populated in useredit.aspx

Only a few records are affected. I checked everywhere this user is and cannot find where their name is blank. Any ideas?
I can't think of why it would be blank in the one place, but populated in the other. If you resave, does the name appear in usersdisp? If not, maybe hit F12 in the browser and inspect where the name should be - perhaps there's a special character in the name that's preventing from showing in the page (but it might still show in the page source).
Tried saving the user page but no dice. Any chance you could share the query or SP that is used to populate that page?
FYI, I ran into this same issue when creating the accounts progammatically via a console app. The full name and all date fields (Created, Last Login, etc.) show blank on the users display page, but have values in the membership database. Also, like Paul mentioned, full name is blank on the display page but shows up when I edit the user.

One other thing I noticed is that the full name field appears to be read-only this way, whereas it's not if I create the user using the solution's new user page. I can change it on the edit page, but when I exit the page it always resets back to whatever it was originally. Weird, huh.
I see what's going on now.

The full name doesn't show on the usersdisp page because it doesn't exist (the user exists in the membership database, but hasn't been added to SharePoint, and the full name is only stored in the SharePoint site collection user profile.)

The name does show on the user edit screen, but it has simply defaulted the full name value to the username, because the full name doesn't exist.
To work around the problem, I will add the user affected to a SharePoint security group from within SharePoint. That fills in the Full Name and set IsInSharePoint = Yes. I then remove him from that group (because he doesn't need the permissions). But sometimes that user will login using FBA and something will happen to remove his full name and IsInSharePoint = No. Maybe it's because I removed him?
The only reason I can think it would show IsInSharePoint = no is if he is logging into a different site collection than the one he was created on. SharePoint user profiles are stored at the site collection level, and don't move across site collections.