Sending e-mails from purchaseorders

[Guido1982]

I want to add an actionlink in Purchaseorders to send an e-mail from there. There is a UI10 field for the account, so I can modify the business action javascript to get the account ID from there. The problem is, is that the window is not present in the DOM. Is there an easy way to get that going and can I use fields from the PurchaseOrder as mergefields in templates I subsequently select?