Cisco Router Port Forwarding Challenge

Hi Experts,

I am having a challenge accessing the exchange server located on the dmz of the cisco ASA5505.
the major challenge is that while i am able to access the exchange server from within the inside network i.e 172.19.30.0/24 network, i am unable to do same from the internet.
i believe i have put in the appropriate configurations in both the Router and the Firewall.
One interesting thing is that it appears that the ports 443, 143, and 25 are not open on the 41.58.X.104 ip address. The only port that seems to be open is the telnet port and i wonder why.
Also i noticed that when i issue a telnet command to the exchange server from the router, it fails to connect. What exactly am i doing wrong.
Kindly help intervene.
I have attached the relevant configs.
Also note that Natting is done on the router and not the ASA.
The ASA has " no nat-control " configured on it.

Regards

 Exchange-Server-Scenario.vsd ASA.txt Router.txt