Spark, slowest chat initiating and connecting from all XMPP Clients

I’m using a CORE i5 PC 4G RAM, WINDOWS XP, when I Power on the PC, all programs start up very fast but spark takes too long time to start, and when it try to connect to the server takes at least 10s - 15s to connect, even in a **1,0Gbps Lan. **

This happen in all the 34 PC of Network.

I’m sure many people here have that issue.

Please, Why this happen??, How can be this fixed??

Please i will like someone to answer this questions