About Spark buddy list problem

We are using spark now for the enterprise. I think this has some problem.

About 50 employees uses spark messanger in our office.

Spark was OK when we use internal database first time. but we set buddy list brings buddies from our enterprise’'s mail server. Sometimes buddy list could not shows list and sometimes it shows them.

We want to see informtion about buddy’‘s log on / out real time. But sometimes it is working and sometimes it’'s not.

If I refreash it, then it shows buddy list when spark doesn’'t show buddy list.

Please give me a answer for solve this problem.