linux redhat as5.4,zimbra602 oss
when i login with the username is lison , every time i got 502 bad gateway, I checked the log an found that the retuest was send to the wrong place :

2010/04/30 10:55:47 [error] 9198#0: *128 connect() failed (111: Connection refused) while connecting to upstream, client:, server:, request: "GET /favicon.ico HTTP/1.1", upstream: "", host: ""

The right address should be, somebody who can tell me how can i modify this address ?