SFB4 behaving wierdly

I finally decided to bite the bullet and try out the IEC timer blocks in the S7 PLC. These are SFB4 = TON (Delay ON), SFB5 = TOF (Delay OFF), and SFB3 = TP (Pulse Timer).
TON behaved strangely. No matter the preset time, the Q (output) would come on immediately the IN bit was set.
Has anyone else had this problem? And if so, have you been able to get around it?
The TOF and TP timers worked as advertised, only the TON caused a problem.
Also, I was using the PLC Sim, not a real PLC to test this.

TIA,

Doug

Doug...you need the hotfix - see this thread:

http://www.plctalk.net/qanda/showthread.php?t=27565

Thanks for that, although I am using a 5.3 rather than a 5.2 simulator. Still, I only bought it a month ago, so I will contact Siemens in the morning.

Thanks again,

Doug