Sending messages is strange ?!

[Bruno]

I am not sure, but it is like i can send private messages to online users only (Or this is what i think). When i try to send a pm to an offline users (i tried with Krose, and Ben but this doesn't worked out) i got an error that looks like:
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INSERT INTO pm (`id`, `f`, `to`, `on`, `b`, `s`) VALUES ('c37khgkitjf', '656', '2', '1184679683', 'here the message i sent', 'A bug, where to place it if noticed ?')
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First the error should be removed, secondly i think there should be a way to output the error in a way that hides the implementation, like ---------Error while sending message---------
I hope this will be posted :)

[hemntjrseth]

I got a similar error message yesterday. It took about 30 minutes but the problem went away.