calcru: negative time ... followed by freeze

Im seeing tons of theese errors myself. Im getting them from tcpserver as 
well as sh

Im using a single processor machine also. Just thought I'd throw in my 2 
cents worth of input

FreeBSD 5.2-CURRENT #0: Sun Jun 20 09:40:31 PDT 2004
CPU: AMD Duron(tm) Processor (1194.92-MHz 686-class CPU)

small sample of errors.. My machine never froze up though

calcru: negative time of 7524 usec for pid 1735 (tcpserver)
calcru: negative time of 4165 usec for pid 1734 (tcpserver)
calcru: negative time of 7445 usec for pid 1733 (tcpserver)
calcru: negative time of 7524 usec for pid 1735 (tcpserver)
calcru: negative time of 4165 usec for pid 1734 (tcpserver)
calcru: negative time of 7445 usec for pid 1733 (tcpserver)
calcru: negative time of 3823 usec for pid 3725 (tcpserver)
calcru: negative time of 8588 usec for pid 3724 (tcpserver)
calcru: negative time of 8863 usec for pid 3723 (tcpserver)
calcru: negative time of 3823 usec for pid 3725 (tcpserver)
calcru: negative time of 8588 usec for pid 3724 (tcpserver)
calcru: negative time of 8863 usec for pid 3723 (tcpserver)
calcru: negative time of 4460 usec for pid 5833 (sh)
calcru: negative time of 4655 usec for pid 5832 (sh)
calcru: negative time of 0 usec for pid 5831 (sh)
calcru: negative time of 4460 usec for pid 5833 (sh)
calcru: negative time of 4655 usec for pid 5832 (sh)
calcru: negative time of 0 usec for pid 5831 (sh)