httpCookies domain="XXXXX" does not hold true when running SSL off a non-default port

I am running an app on a non-default ssl port which is reverse proxied via IIS aarV2 to a non-ssl address.
IIS 7.0.6
.Net 2
AAR v2
https://www.domain.com:8080/sampleapp/default.aspx
<rule name="ReverseProxyInboundRule2" patternSyntax="Wildcard" stopProcessing="true"> <match url="sampleapp*" /> <action type="Rewrite" url="http://127.0.0.1:8383/sampleapp{R:1}" /> <conditions> <add input="{HTTPS}" pattern="ON" /> </conditions> </rule>

Forms authentication keeps redirecting me back to login page.
<httpCookies domain="www.domain.com" requireSSL="true" httpOnlyCookies="true" />

If i remove the domain security config for http cookies then it is sucessfull.

Anyone can shed some light? Seems to be a ...