Operating system name and version: CentOS 6.1 (64Bit)
Version of smsd: v3.1.14
Smsd installed from: sources
Name and model of a modem / phone: Multi-Tech Multimodem MTCBA-G2-EN2
Interface: Ethernet

It seems that we have a problem with the login to the modem. When we use "admin" as login and "admin" as password it works but with error messages. If we use another password than "admin" we receive the following errors, of course we changed also the password on the modem and checked the login with telnet.

Log:
2012-01-06 14:17:24,2, smsd: Smsd v3.1.14 started.
2012-01-06 14:17:24,2, smsd: Running as icinga:icinga.
2012-01-06 14:17:24,7, smsd: Running startup_check (shell): /var/spool/sms/incoming/smsd_script.KiiGDU /tmp/smsd_data.Y5ZHv7
2012-01-06 14:17:24,7, smsd: Done: startup_check (shell), execution time 0 sec., status: 0 (0)
2012-01-06 14:17:24,4, smsd: File mode creation mask: 022 (0644, rw-r--r--).
2012-01-06 14:17:24,5, smsd: Outgoing file checker has started. PID: 2021.
2012-01-06 14:17:24,7, smsd: All PID's: 2021,2022
2012-01-06 14:17:24,5, GSM1: Modem handler 0 has started. PID: 2022. Will only send messages.
2012-01-06 14:17:24,6, GSM1: Checking if modem is ready
2012-01-06 14:17:24,7, GSM1: Telnet: Got DO for 24 (0x18), answering WONT.
2012-01-06 14:17:24,7, GSM1: Telnet: Got DO for 32 (0x20), answering WONT.
2012-01-06 14:17:24,7, GSM1: Telnet: Got DO for 35 (0x23), answering WONT.
2012-01-06 14:17:24,7, GSM1: Telnet: Got DO for 39 (0x27), answering WONT.
2012-01-06 14:17:24,7, GSM1: -> AT
2012-01-06 14:17:24,7, GSM1: Command is sent, waiting for the answer
2012-01-06 14:17:25,7, GSM1: Telnet: Got WILL for 3 (0x03), answering DONT.
2012-01-06 14:17:25,7, GSM1: Telnet: Got DO for 1 (0x01), answering WONT.
2012-01-06 14:17:25,7, GSM1: Telnet: Got DO for 31 (0x1F), answering WONT.
2012-01-06 14:17:25,7, GSM1: Telnet: Got WILL for 5 (0x05), answering DONT.
2012-01-06 14:17:25,7, GSM1: Telnet: Got DO for 33 (0x21), answering WONT.
2012-01-06 14:17:25,7, GSM1: Telnet: Got WILL for 3 (0x03), answering DONT.
2012-01-06 14:17:25,7, GSM1: Telnet: Got WILL for 1 (0x01), answering DONT.
2012-01-06 14:17:31,7, GSM1: put_command expected (OK)|(ERROR), timeout occurred. 1.
2012-01-06 14:17:31,7, GSM1: <- Login: AT Password: Invalid Login name (AT) Login: red85zz Password: Invalid Login name (red85zz) Login: red85zz Password:
2012-01-06 14:17:31,7, GSM1: -> .
2012-01-06 14:17:31,7, GSM1: Command is sent, waiting for the answer
2012-01-06 14:17:36,7, GSM1: put_command expected (OK)|(ERROR), timeout occurred. 2.
2012-01-06 14:17:36,7, GSM1: <-
2012-01-06 14:17:37,7, GSM1: -> AT

/etc/smsd.conf:
devices = GSM1
logfile = /var/log/smsd.log
loglevel = 7
blocktime = 60
user = icinga
group = icinga
infofile = /var/run/sms/smsd.working
pidfile = /var/run/sms/smsd.pid

[GSM1]
device = @192.168.61.233:5000
telnet_login = admin
telnet_password = red85zz
keep_open = yes
incoming = no
baudrate = 2400
send_delay = 0
rtscts = no
cs_convert = yes
report = no
regular_run_interval = 300
regular_run_cmd = AT+CREG?;+CSQ;+COPS?
regular_run_statfile = /dev/shm/sms_stat