Crossdomain.xml

We are trying to access crossdomain.xml through Adobe Flex. We created ZFLEX bsp application in ECC and imported crossdomain.xml as MIME types which created service automatically in SICF under node /default_host/sap/bc/bsp/sap/zflex.

When we are trying to access with URL http://FQDN:8000/crossdomain.xml it works some time and it requests authentication some time.

We would like to access it always without entering authentication but seems like it is intermittent.

An ideas?

Thanks,

Miral.