Have been getting the following error message on Storage Manager Engine

12/28 11:20:11 2: HTTP_EventIn: Invalid signature of POST data from client (10.1.0.94) request.
12/28 11:22:57 2: HTTP_EventIn: Invalid signature of POST data from client (10.1.0.94) request.
12/28 11:25:29 2: HTTP_EventIn: Invalid signature of POST data from client (10.1.0.94) request.
12/28 11:28:35 2: HTTP_EventIn: Invalid signature of POST data from client (10.1.0.94) request.
12/28 11:31:37 2: HTTP_EventIn: Invalid signature of POST data from client (10.1.0.94) request.
12/28 11:34:25 2: HTTP_EventIn: Invalid signature of POST data from client (10.1.0.94) request.
12/28 11:37:33 2: HTTP_EventIn: Invalid signature of POST data from client (10.1.0.94) request.
12/28 11:40:47 2: HTTP_EventIn: Invalid signature of POST data from client (10.1.0.94) request.
12/28 11:43:53 2: HTTP_EventIn: Invalid signature of POST data from client (10.1.0.94) request.
12/28 11:46:51 2: HTTP_EventIn: Invalid signature of POST data from client (10.1.0.94) request.
12/28 11:49:59 2: HTTP_EventIn: Invalid signature of POST data from client (10.1.0.94) request.
12/28 11:52:51 2: HTTP_EventIn: Invalid signature of POST data from client (10.1.0.94) request.

and this on the event monitor

009-12-28 11:43:53 4: ES: SendTransactionData: Transaction data signature is invalid; Result = 5.
2009-12-28 11:46:51 4: ES: SendTransactionData: Transaction data signature is invalid; Result = 5.
2009-12-28 11:49:59 4: ES: SendTransactionData: Transaction data signature is invalid; Result = 5.
2009-12-28 11:52:51 4: ES: SendTransactionData: Transaction data signature is invalid; Result = 5.
2009-12-28 11:55:23 4: ES: SendTransactionData: Transaction data signature is invalid; Result = 5.
2009-12-28 11:56:21 4: HB: Successfully sent last 15 heartbeats to the Engine.
2009-12-28 11:58:36 4: ES: SendTransactionData: Transaction data signature is invalid; Result = 5.