This is likely too general a question but, googlin' around for hours, I haven't found anything. 
I have a web application based on zope/plone/python where zope/plone is used, among other things, as a soap and xml-rpc web server.
However sometimes (when response is "big") my xml-rpc response is truncated(*) as if the xml-rpc protocol could not handle more than "x" characters (or bytes).
Is anyone aware of this?
Bonus question:
If you were in my shoes, what would you look for during "investigation"?

I've also added "python" tag because zope/plone components are written in this language and, maybe, there are some pythoners that could help me.
(*) Received to caller (that is onto another network, for example) truncated.
Be aware that control characters in response content could block the parsing of the xml and, for example, just cut data. At least this is what happened to me.
Maybe I'm a little bit late, anyway I spent so much time today on this issue that I would like to share what I've finally found.
At the beginning I've tried to check if there is some limits somewhere: in xml-rpc server php code, in my apache http server, in the python xml-rpc client (base on incution xml-rpc library)... but found nothing.
Than I begun searching for hidden control characters in the response content and finally found a record separator ASCII character. Deleted and all worked well.
Does xml-rpc have some kind of "response length limit"?