TCL clock scan

the below shown clock manipulation works well in Linux machine which has TCL 8.5. But when i use the same on the SunOS which has the TCL8.4 , I am getting the error "bad switch "-format": must be -base or -gmt".

For some reason, I am not able to upgrade my TCL 8.4 to 8.5 in SunOS.

Can anyone please help, how can I make it work in TCL 8.4 as well?????

The Commands are given below and what I am trying to achieve through these commands is to advance the system date by one more day.

$today contains the value "2012 06 15 14 39 20"

set today [clock scan $today -format "%Y %m %d %H %M %S"]
set tomorrow [clock add $today 86600 seconds]
set victim [clock format $tomorrow -format "%a"]
set tomorrow [clock format $tomorrow -format "%m%d%H%M"]
send "sudo date $tomorrow\r"

Thanks