Problem executing nohup

I am trying to submit background jobs using the nohup command on a client system where my session is running under a "master shell" (BASH). If I try to nohup the actual job (ie: nohup MYJOB.BAT > MYJOB.LOG 2>&1 &) the command will fail with a return code of 126 and a "permission denied" message. However, if I submit the job without nohup, then nohup the process id, it will work.

In other words, I submit the job without nohup:

. MYJOB.BAT > MYJOB.LOG 2>&1 & (the ". " is required because I'm running under the master shell script)

I then obtain the process-id, which we'll say is 12345, and nohup the process:

nohup -p -Fa 12345

this will send the no hangup signal to the process successfully.

Does anyone have an idea as to why the nohup will operate on the process id but not the job itself? I know it's not related to nohup.out since I'm redirecting all messages to MYJOB.LOG. Unfortunately, this client is located halfway around the world and technical support is limited to say the least, so I'm not sure what is going on with this "master shell".

Thanks for your help!