CDR Time Stamps for Forwarded Calls

I have noted the following strange scenerio

Two Mobile Stations MS1,MS2 MS1 is forwaded to MS2 and both are roaming in another country. A call is made to MS1 from the VPLMN and thi is what happens

01:34:32 GMSC receives a call for MS1
01:34:32 GMSC forwards the call to VMSC for MS2
01:33:19 VMSC receives the forwarded call
MS2 MTC record timestamp 73 sec
onds before the original call for MS1

has anyone seen this kind of problem?
These records were generated by the SIEMENS D900 switch