Hi ..
to allow access from outside to inside you need to perform 2 steps.
1.- Configure a static nat .. in your case it will be somehting like this.
static (inside,outside) Public_IP Private_IP netmask 255.255.255.255
where inside is the name of the interface where your servers are located.
outside is the name of the interface connected to your in-house network
Public_IP is the ip address that the in-house network will connect to reach your internal servers (Private_IP).
2.- You need to allow access on the access-list applied to the outside interface. SOmething like this.
access-list Outside_Access_In permit tcp any host Public_IP eq 23
access-group Outside_Access_In in interface outside
I hope it helps .. please rate if it it does !!!