Invoice amount not updated with tax amount

Hi All,

I have setup non inclusive tax rate and updated the same at site level.  When I create a invoice in AR - item 100  and calculate tax, tax amount is added to the invoice amount.

But in AP, when I create an invoice, header amount 100 and line amount 100 and calculate tax, tax is calculated and a new line is created, the tax amount in header region gets populated but not  added to the header amount...  Because of this, the invoice goes to system hold.

Please let me know what might be the issue.

Regards,

Arun