Alex,
What is the security level for these interfaces? Same security?
Pls. read here: http://www.cisco.com/en/US/docs/security/asa/asa80/configuration/guide/cfgnat.html#wp1042673
Logically what you are trying to do should work even if it is same security.
Now, you need to provide translation for the other way as well that is why your static works (static is bi-directional) and nat/global is not.
global (inside) 98 10.153.98.1
nat (outside) 98 10.255.0.0 255.255.0.0
you also need
nat (inside) 1 10.153.98.0 255.255.255.0
global (outside) 1 interface
#######################################
If outside security is lower than the inside the, you need the "outside" keyword to translate from low to high.
http://www.cisco.com/en/US/docs/security/asa/asa80/command/reference/no.html#wp1737858
outside (Optional) If this interface is on a lower security level than the interface you identify by the matching global statement, then you must enter outside. This feature is called outside NAT or bidirectional NAT.
-KS
