I'd like to send the java script: javascript:NextPage(1) to a website from the webviewer. Is there any way to send this via post url. Thanks in advance

I think you need to take a look at this plugin it has been very helpful to me:

http://www.monkeybreadsoftware.de/filemaker/index.shtml

You want to send a javascript command via a post url... you know that doesn't make a whole lot of sense right?

POST -> Is by its nature not sent via a URL (though there is a work around for this which can be provided if required)

Sending something via a url implies that the page should be refreshed in any case which sort of eliminates the purpose of javascript especially given that in most cases a variable's life in JS will not extend past that particular page load.

The page is likely expecting a particular variable either submited via the URL (or $_GET) or otherwise via the POST method (possible to simulate via a URL) to set the initial page if that is in fact what you're trying to achieve.

Bottom line is please be more specific with what you're actually trying to achieve. Submitting the URL you're trying to play with would probably also be useful.