You may be using package globals to store your data instead of properly scoped object containers such as a blessed lexical hashref. But this response is about as reliable as if you had taken me to a room full of people I don't know, put a blindfold on me, spun me around six times, and asked me to point to Kevin. We need to see code posted to be able to disect what you've done wrong. I recommend boiling the problem down to no more than 20 or so lines of code that replicates the problem and posting it here.