SPF Settings when using other FROM_MAIL (Domain)

[PlayCayP]

Hello,

I have just created a mail account within Plesk 11.

This I would like to use for several domains (FROM_MAIL).

But I always receive SPF:Neutral

Only when the domain name is used, that the mail account has been created with, then it shows SPFass

Is there any way to also let other domains (FROM_MAIL) be used to send mails with SPFass?

Shouldnt this already allow all domains to send mails?

v=spf1 +a +mx +ip4:xx.xx.xx.xx -all

I hope that someone got an idea.

Thank you.