Hello ekzarov,
When I try to upload the .cab file to MOSS 2007, I didn't got any error.
Here are the steps I followed:
1. Designed a form in IP2007 with Browser Compatiable features and saved the form to the local machine.
2. Open the XSN in the design mode which is saved to the local machine and publish it to any Form Library which is in the MOSS 2007.
3. Click on Settings and then click on Modify form library and then click on Advanced settings and then Click on Edit template.
4. Extract the form files from the template which is opened.
5. Open the manifest.xsf in the design mode from the resource files which is saved locally.
6. Save the solution to the local machine as Template1.xsn
7. Change Template1.XSN to Template1.cab
8. Open any form library in MOSS 2007 and click on Upload Document and browse to the location where Template1.cab is placed and click on "OK".
The CAB file is uploaded successfully to the form library in MOSS.
Hope this helps, If not can you give me more details about you are trying to do?
krishna chaitanya tedla
InfopathDev, India.