Problem with pass argument to Subroutine

Hello Experts.
I defined a simple subroutine and use it in following ways:

exten => 5000,1,GoSub(subTest,s,1(5000,30))

exten => s,1,Background(hello-world)
exten => s,n,Dial(SIP/${ARG1},${ARG2})
exten => s,n,Playback(digits/5)
exten => s,n,Hangup()

When i call 5000, i hear “Hello-world” and then call ended. I dont pass argument to sub in asterisk. When i went to asterisk console, I saw this error :
[Apr 16 02:30:31] WARNING[1719]: app_dial.c:1228 dial_exec_full: Dial argument akes format (technology/[device:]number1)
What is my problem? and how can i pass argument to sub?
Note that i dont have this problem with Macro and I use Asterisk 1.4.44
With Regards.Mojtaba