Hi Anantraj,
No it was space ' ' at the end which was getting the length more than the structure it should be.
Now, its resolved.
Steps in my case :
1. Put break point at fm 'ssfrt_write_error' . see message variables where in the smartform exactly error is coming.
2. For me it was text in the template where size of text was overflowing template length.
3. Put (C) at the end of the text message to make it condense.
Thanks for quick replay.