Mozilla drag and drop problems

Has anyone experienced drag and drop problems in Mozilla 1.5-0? If I attempt to drag a message to another folder, moz locks up X, and only mouse movement is functional. I also tried highlighting some text in the web browser and got the same symptom. I think it thought I was trying to drag the text but I am not sure of that. If anyone has experienced this or has found a fix. please let me know. Thanks, Darrell Cormier