1. N.I.Act precribes it as an offence ONLY when "funds are insufficient"
2. Similarly IF signature is incomplete or is different, AND "IF" the Bank Memo does not say "funds are insufficient", THEN the court would not take it as an prosecutable offence, "PROVIDED", you prove that on date of return of cheque there was sufficient balance in account. ELSE it would be taken as "funds insufficient" irrespective of the remark on the Bank Memo.
3. ALSO, to be on the sly & defensive, declare that the cheque was misplaced /stolen /blank unsigned cheque forcefully taken and that the cheque was not signed by accused. This might require some pre-mediated efforts (police NC, Manager's affidavit/statement .... )
Keep Smiling .... Hemant Agarwal