Dosemu stsrts only one time in Putty

Hi All,
I new on the list so let me say that You do a great job!

As I say in subject i observe strange behavior on Ubuntu Server 8.04 LTS 
with Dosemu installed.
After installation dosemu starts only one time with properly working 
screen on Putty terminal. I see Dosemu welcome message when I invoke it 
via dosemu -t command.
When I exit to linux and start Dosemu again I see only black background 
with cursor block in strange position, but program works ok because when 
I type exitemu I back to linux prompt.
Only machine restart let me run Dosemu again. Exit Putty and start new 
session not work.
Software used:
Linux Ubuntu server 8.04 LTS
Dosemu 1.4.0 from Ubuntu repository installed via aptitude with no 
tweeks in config files.
Putty for Windows version 0.60

Could Yoy give me some direction what I can change to make it working?

Regards,
Tomasz Skorupa