in reply to Re^3: How to use IEAutomation with iframes?
in thread How to use IEAutomation with iframes?

Using the URL of the relevant iframe as the IEAutomation source URL I can identify and fill in the account name textbox with this snippet:

$ie->getTextBox('name:', "account")->SetValue($user)

Still need to figure out how to locate it from the parent iframes...