K2.2003 InfoPathServices: problem with size of InfoPath form

We have multiple document approval process started from InfoPath form with attached documents. Everything works fine when documents are not too big, but when a user tries to submit large document (30Mb ppt for example) submit is unsuccessful. First I increased timeout in InfoPath, so now I m getting K2.net web service problem
I m increased maximum .net upload file size and timeout value in web service c:program filesK2.net 2003K2WSInfoPathServiceweb.config:

<httpRuntime maxRequestLength="100000" executionTimeout="900" />

Is there limit on how large can be InfoPath forms submitted through web service, or I can somehow manage this limit?