Not able to 'SAVE AS ' the theme

Hi ,

I am trying to make my own theme from one of the SAP delivered theme by 'SAVE AS' option . But towards end of the saving process I was getting an error alert in a windows popup saying that 'Exception caught while dispaching result :null ' . Have any one met the same situation . Let me know as this is very crutial .

The portal version we have installed is EP6 SP12 on UNIX machine.