Can't send to hotmail via squirrelmail

[ianevans]

Just wondering if anyone here using Squirrelmail for their webmail have had problems sending email to hotmail. Here's a summary of our situation:

1) Email sent from our domain to hotmail.com IS delivered if sent via Outlook or Thunderbird

2) Email sent from our domain to hotmail.com IS delivered if sent via a script using the PHP5 mail() function.

3) Email sent from our domain to hotmail.com IS NOT delivered if sent via Squirrelmail

Could Hotmail be acting upon some SM header or anything like that?

We do have an SPF record, reverse DNS is setup properly, etc.

[piatkow]

I am not up to speed on the technicalities but I know that Hotmail do seem to regard emails as suspect if they are "from" a domain name but sent from another webmail service (AOL seem to be much the same).