xmpp.client.idle is a system property, the default if it is not set will be afaik 30 minutes (1800000 ms, you should add the new value in ms) and you need to add it on page /server-properties.jsp. I hope that this is the right value, maybe you can set it first to a low value to make sure that this makes the problem worse.
I wonder whether one must restart Wildfire or not after changing the value.
Would the xmpp.client.idle behavoir be more agressive on a memory-starved server?
I ask because we have some tkabber clients on our new (and memory troubled) server that get idled out (despite presences updates and such) at 30 minutes (not a very graceful idle out - just a FIN-ACK with no ‘‘we are kicking you off you loiterer!’’ type message). However, on weekends when the server is not so busy, they don’'t get kicked off.
I plan to set the xmpp.client.idle value to a -1 to stop this all togethar. Did that change work for others?