SAP NetWeaver Portal won't open through AirPort Extreme

Hello,

I am trying to access this site: https://ess.sobeys.com/irj/portal

When my iMac is connected to the internet through our AirPort Extreme, the site will not load. It will also not load on any device (iPod, iPhone) connected to the network created by the AirPort Extreme.

When I bypass the AirPort and connect the iMac directly to the internet, the site opens.

Also, when I turn off the Wi-Fi on my iPhone and use 3G data, the site opens too.

I can not find any info online about this. I think it may have to do with ports on the AirPort Extreme.

Any help would be appreciated.

Thanks,

Patrick