Shell Programming and Scripting

I have a program (say, MyProgram) written in Bourne-shell script, but at some point it calls another script written in pearl, as illustrated below:

#!/bin/sh
.....
case $x in
1) ConfigSystem1 ( b-shell script)
2) ConfigSystem2 ( pl)
3) ConfigSystem3 (b-shell)
....

Then I create another script (call ConfigSystem) in an attemp to capture the screenshot & save it in a dated log file:

#!/bin/sh
datestamp=`date +%y%m%d_%H%M%S`
MyProgram 2>&1 | tee ../logs/ConfigSystem_$datestamp.log

If I run ConfigSystem, it hangs at the point where the pearl script is called.

If I run MyProgram, it is fine (but with no log)

Why does it hang on the pl script or is there another log utility that can work in this case?

Thanks in advance!!