LS2J Error: Threw java.lang.NoClassDefFoundError: Webretriever

The error in subject occurs when few users try to fetch data from BluePages. Rebuilt of perweb.nsf and notes cache didn’t solve it. What could the problem’s cause could be?

Subject: Solution

There is solution for your problem.

http://ibmforums.ibm.com/forums/message.jspa?messageID=1249570&tstart=0