Email Signed Wrong (un-repeatable though)

i had something odd happen to me a second ago.  I sent an email from gmail and it got signed, after clicking send and typing it password, it took firefox about 15-20 seconds before coming back (delay/lag in ajax request?) and if i look at the email in sent mail it says Signed Wrong.

I sent another email right after this to myself and it was in fact signed properly.

fluke due to the lag in ajax/send request? but i don't see how that would effect the signing.