A Deal Reject has to be sent using com.apama.oms.OrderUpdate event with the extraparams should contain the key "RejectCode" with value one of the following:
Code
Description
4007
Quote has expired - either superceded or timed out.
4008
Decimal places on rates unsuitable.
4009
Trade amount not valid.
4010
Credit limit checks failed.
4011
Generic rejection code - use for miscellaneous failures.