connection problem above head

hey,
i got verry strange problem
me and my best friend wanted to play on my gunz private server ese we started
the launcher no problem's (yes i'm using hamachi) we can talk in gunz and whisper to eatchother
but when we start a game and we are playing i see an connection prob icon above his head
and he sees it above my head i dont know what's wrong. dos he need to portforward hamachi?
or what i dont understand this problem he dos not has this problem with other gunz
but other gunz he played diddent have hamachi where port forwarded once.
anyone can fix this or help me pm me.
or e-mail me ad msn:(ghostrevan@hotmail.com):?: