After installing a Lotus Quickr 8.0 (Domino Services) server and connecting it to a Lotus Sametime 7.5.1 CF1 server the chat link on the right hand side of a place was not working.
Normally this link should display a small window where you can see all users who are currently online and you should be able to directly start a chat with these people.
Instead of this I only got a window with a small red "X" inside and a unspecific error message in the Java console.
There is already a hotfix for Lotus Sametime available for this problem which you can obtain via Lotus support. You should reference to SPR# JYYG6ZZD4V. If you got the fix you should overwrite the existing files "CommRes.jar" and "STComm.jar" in the "..Quickplace\Peopleonline" directory which you created before as part of the Quickr/Sametime integration.
After restarting your Sametime server the Chat link in Quickr should work as expected.
The SPR is already mentioned in this KB article as being fixed with Sametime 7.5.1CF1 but this seems not to be true in this particular case.