Activiti Probe should have the capability to do file upload and deploy a business archive.
Ideally, this should be guarded with authentication in such a way that also this feature could be leveraged by Activiti Modeler and Activiti Designer without introducing security problems.
For how to do file upload, i think i just saw an Activiti Cycle commit which was about uploading an artifact (at least i think). So that could provide some good reference material to look at before starting this. http://fisheye.codehaus.org/changelog/activiti/?cs=1195