The Selenium IDE does not record anything from this websites "http://suppliers.inwk.com". You may not have credentials to get login access, but if you can get the login page itself recorded in Selenum IDE, then I think we can come to the root cause, or atleast get a clue.
If I save the page to local machine, and open the page, and try to record it works. Seems to be like this line in the source of that page is the root cause. Can any of you figure out the nature of issue coming from this line?
<script type="text/javascript" language="javascript" src="com.iwprint.vendorportal.VendorPortalClient/com.iwprint.vendorportal.VendorPortalClient.nocache.js"></script>
also, FYI: this site is made using gwt (GWT). Is that what makes it not compatible with Selenium?