Account Bank and Exchange transactions are very slow

Is anyone else having the problem that items put into or taken out of the
account bank can take several minutes to actually transfer?

Also, I just started experiencing the same slowdown in the processing of
buying or selling of goods on the exchange.

Is this a transaction problem between servers due to load, or something else?

Also, possibly related, the "Login failed for unknown reason" error is back.

Edit: It appears that some transactions go through after several minutes,
while others are just "lost", and never complete. *sigh*