CallerOrigin is deprecated in CRM 2011/CRM2013.
The alternative is to create an attribute and set it based on your request (so if you update the record by a plugin you set the field to "plugin", by web interface you keep empty or use another string, or use a boolean field, false web interface,
true plugin)
if you are onpremise there is also this alternative:
http://a33ik.blogspot.com/2012/06/callerorigin-in-plugins.html
but I suggest the attribute
My blog: www.crmanswers.net -
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