Need to disable SSH version on a cisco 2600

We have a Cisco 2600 series router which is using SSH for remote access. WE had an outside firm do a security scan and they came back with some results including that I need to disable SSH version 1. I did some research and it seems that should be easy by simply putting in the ip ssh version 2 command, however that option is not available on my router IOS. When I type ip ssh ? the results do not show "version" as an option..Does anyone know how to disable SSH v1 when that command is not available...Here is my show ver:

Cisco Internetwork Operating System Software
IOS (tm) C2600 Software (C2600-IK9O3S3-M), Version 12.3(26), RELEASE SOFTWARE (f                                                        c2)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2008 by cisco Systems, Inc.
Compiled Mon 17-Mar-08 15:23 by dchih

ROM: System Bootstrap, Version 12.2(10r)1, RELEASE SOFTWARE (fc1)

99cent_Bkup uptime is 3 weeks, 3 days, 5 hours, 22 minutes
System returned to ROM by power-on
System image file is "flash:c2600-ik9o3s3-mz.123-26.bin"