different Exchange server name for internal/external access

[neikt]

I have the following problem with iphone Exchange ActiveSync:

Every time I go to the office I have to change the “Server” name on iPhone’s Activesync settings to the internal name used by our server (IRA.mydomain.com). And then when I go to another wifi network outside the company I have to change again the ‘Server” name to the external name used by our server for outside access (ATHINA.mydomain.com). Until I make this switch to server names on iphone between inside and outside wifi networks all contacts and calendars are empty.

I have tried the DNS setting on iphone by adding external DSN addresses but this doesn’t work. Although this way I get internet to work all the time, email contacts and calendars don’t work properly without the use of the correct “Server” name. THey are auto-deleted all the time.

Is there any way to solve this by making the external name of our server accessible from inside the corporate network as well? Or any other suggestion?

Please find some info which will give you an idea of the network structure.

Thank you in advance.

Hardware + Software:

·1 Cisco ASA Firewall
·1 Windows Server 2008 - Exchange 2007 as Mail Server called IRA.mydomain.com
·1 Windows Server 2003 as Domain Controller/DNS Server called AdDns.mydomain.com

I include an example of the configuration for Outlook Web Access which works flawlessly:

Internal name for OWA:
https://IRA.mydomain.com/owa with internal IP 192.168.0.6 / external IP xx.xxx.xxx.222
·Pinging IRA.mycompany.com [from inside the corporate network] returns
Pinging IRA 192.168.0.6 ….
Reply from 192.168.0.6

·Pinging IRA.mycompany.com [from outside the corporate network] returns
Destination Unreachable

External name for OWA:
https://ATHINA.mydomain.com/owa
·Pinging Athina.mycompany.com [from inside the corporate network] returns
Pinging Athina 192.168.0.4 ….
Reply from 192.168.0.6 (ie reply comes from IRA)

·Pinging Athina.mycompany.com [from outside the network] returns
Pinging Athina xx.xxx.xxx.222 ….
Reply from xx.xxx.xxx.222 (ie reply comes from external IP of IRA)