double variable act weird in DVRRDK_03.50.00.05 and DVRRDK_04.00.00.03

Hi guys.

I found some weird things in different RDK versions,here is my code:

gettimeofday(&now,NULL);
mnow = (now.tv_sec*1000 + now.tv_usec/1000);
printf("==mnow %f\n",mnow);
unsigned int MySend(unsigned int u32, char *pData, int s32DataSize, unsigned int u32TimeStamp)
{
       printf("u32TimeStamp:%d\n\n",u32TimeStamp);
}

DVRRDK_03.50.00.05 print:

==mnow 1141741080.000000
u32TimeStamp:1141741080

==mnow 1141741089.000000
u32TimeStamp:1141741089

DVRRDK_04.00.00.03 print:

==mnow -540595977.000000
u32TimeStamp:0

==mnow -540595913.000000
u32TimeStamp:0

it seems like RDK3.5 is right,RDK4.0 is wrong.

anyone see this before???