"Your browser does not support cookies" wehn logging in from a different url

[em_bi]

When login-informations are send from a different url (e.g. I wanted to place a login-form to the webmailer on my main-site), roundcube states that my browser (tested with Firefox, IE, Konqueror, Opera) does not support cookies. When I then login from the roundcube-url, everything is fine.

Environment:
Main-site: http*mainsite.com
Roundcube: http*roundcube.mainsite.com

Used form:

<form name="form" method="post" action="http://roundcube.mainsite.com/">
<input name="_action" value="login" type="hidden" />
<table><tr>
	<td class="title"><label for="rcmloginuser">Username</label></td>
	<td><input name="_user" id="rcmloginuser" size="30" value="" type="text" /></td>
</tr><tr>
	<td class="title"><label for="rcmloginpwd">Password</label></td>
	<td><input name="_pass" id="rcmloginpwd" size="30" type="password" /></td>
</tr></table>			
<p><input type="submit" class="button" value="Login" /></p>
</form>

Can this be confirmed and are there any ways around this?

[till]

I think the problem is the session that is created even when the "login" is only shown.

$_SESSIONtemp? is what's probably holding you back.

[till]

I cannot reproduce this with the latest version from SVN. I have an external login form and it works just fine.