POST cross domain https in flex code faild

Question

I have added https: / /catherine.mob.dev/crossdomain.xml:

<!DOCTYPE cross-domain-policy SYSTEM "http://www.macromedia.com/xml/dtds/cross-domain-policy.dtd"&gt;
<cross-domain-policy>
<site-control permitted-cross-domain-policies="all"/>
<allow-access-from domain="static.mob.dev" to-ports="*" secure="false"/>
<allow-http-request-headers-from domain="static.mob.dev" headers="*" secure="false"/>
</cross-domain-policy>

And my flex swf is under this url: https: / /static.mob.dev/123091/en/piapp/applications/calendar/Main.swf

In this Main.swf code, I post a xml string to https: / /catherine.mob.dev/data/v1/picorp.com/core/appointment, In firebug 403 forbidden comes out.

If I use GET, it works, and if I use http, it works, and if I POST https in ajax code, it works.

BTW, before I POST, I have login to my application, and I even call Security.loadPolicyFile(.../crossdomain.xml) in flex code.

here is flex error log: Error: [RPC Fault faultString="HTTP request error" faultCode="Server.Error.Request" faultDetail="Error: [IOErrorEvent type="ioError" bubbles=false cancelable=false eventPhase=2 text="Error #2032: Stream Error. URL: https: / /catherine.mob.dev/data/v1/picorp.com/core/appointment"].

Why I cannot POST cross domain https in flex code? how to solve it?