Custom modulo attempt to reload

[alexist]

Hi!
I had wrote a module which is launched by generic agent everytime a ticket is created in some queues.
several times the module don't run and i find this record in the system log: Attempt to reload Custom/Kernel/Modules/calcRoundRobin.pm aborted.

i noticed that when i do any change in the program this error happens, that's ok. but sometimes it ocurres after the module was written and good runnings was

ideas?
thanks