Hi Manoj,
This looks like a custom field. I guess the 'easy answer' is that if you escaped the backward slash char then it will work, but I guess you need this character.
It probably will work better if we work this out via a support case. Will you be able to open up a support case, then reply back here with the case# . I'll pick up this case and work with you.
I'll want to reproduce this, so I'll need to get from you the definition of this custom field, and understand how you enter the values to this field and what value you're entering.
Will you be able to open a support case for this?
Thanks,
Sagi