Question : Infopath 2007 with SharePoint Drafts

So I have a SharePoint site with an infopath document library. I have a workflow with all intents and purposes tracks a form through an approval type process. They would like for there to be a save option, which would not start the workflow. This operation would simply save the form in the document library within sharepoint. This form can then be completed at a later time and submitted.

So my question is this, is there a non-code based solution to this? If so, does that solution work with the fact that I do have controls which are required ("cannot be blank")? If there are only code based solutions do you know of a good tutorial for this? I found a couple code based solutions out there, one didn't take into account required fields and the other just saved an xml file to the document library which did not behave like an infopath form.

Answer : Infopath 2007 with SharePoint Drafts

If you create a field that stores the "State" of the form, and update this field on the final submit and promote it. You could have draft, submitted, reviewed, whatever.
Then I believe your workflow could look at this value conditionally and react accordingly.  I am not a SP workflow expert so I am not sure.

I have done lots of workflows, codelessly, within InfoPath itself and have used a similar approach successfully.