IDOC structure difference in Webmethods 7.1.1

We are upgrading SAP Integrations from webMethods 4.1 to 7.1.1

This is an interface which send IDOC (ALE) data from CCS to Integration Server. ALE listener notifcation was created and the notification document which was created automatically matches with expected idoc structure. When we created IDOC in SAP, the data received has different format. For each segment in SAP the notification document is a structure, but we are receiving array of structures. In 4.1 integration we are receiving only single structure but in 7.1 it is received as an array of structures. We retriggerred existing IDOCS and does not look like SAP problem. Anybody seen this behaviour in 7.x? Any tips to rectify the problem will be highly appreciated.
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