Hi guys,
I was able to find one freeware called PDF -XChange Viewer. Using this, you can open the fillable forms, edit the contents and save them without losing what you typed. The product page has a disclaimer that warns that it may so happen that at times, Acrobat reader cannot open the files saved by this software. So, use it at your own risk.
Here is the download URL...
http://www.tracker-software.com/product/pdf-xchange-viewer/download