httpd eats processor

hi there, it's me again i wrote a library. there are about 30 classes, each has less then five fields, some methods... there are such a configurations of usage of these classes, that AFTAER my php page is processed, the 'httpd' process eats all processor (httpd hungs up) and it's hunging till i kill it. i noticed, that when i'm changing the reference usage (in some places i add and remove '&') i can control the problem (i mean, httpd doesn't hung up) but this is not a solution -> i never know if my next usage of class will couse error on httpd. is this known problem ? or this happens only to me ?? please help me, becouse our big project will be based upon this classes library :(( dariusz malinowski