Missing subject line in BW Process Chain Messages

Hi Experts!

We are using BW3.5 (Support pack 16) process chains. There are a number of process chains and almost every thing is working fine.

But 2 process chains, send message without any subject into the email.

I did a number of tricks e.g. reactivated/rescheduled process chains, removed from scheduling and rescheduled, also deleted and recreated the message but nothing is working.

Did any one else face the similar problem?

Please let me know,

Thx

Praveen