Internet Explorer proxy support in Win7PE_SE

Hi,
I'm trying to build a disc with Microsoft System Sweeper keeping the iso size as low as possible by leaving the definitions out - I was hoping to have who ever uses the disc to download the definitions as needed but we use a proxy server at work and IE doesn't prompt for credentials, it just blocks me.  Am I missing some dependencies???

IE Proxy Settings script is not enough for your proxy?

the proxy settings script seems to only set the proxy settings in ie rather than doing it manually. it knows theres a proxy there bt doesnt prompt for credentials to authorise it on the proxy. that functionality seems to be missing.

This is about features about utility, xpeinit.exe, not plugin itsself..
http://sourceforge.net/projects/winpe/files/Windows%20XPE/Windows%20XPE%20v1.0.7/

yes password function missing 
yes "after boot PE" change missing

so far, nobody asked for these 

well, it will be nice if you can figure out ( and share ) a way (utility etc.) that fits proxy requirements you have,
 and that works nicely on network environment with your PE  .....

Does it HAVE to be Internet Explorer?  There are standalone browsers out there with proxy support that works in PE, QTWeb for example

As far as I know:
 proxy setting of IE is in fact default proxy settings of running Windows (system),
  and browsers use system proxy settings as default 

Well better you try and see yourself  with Win7PE SE
 let us know how it works