eu finalmente consegui fazer isso usando os seguintes shell scripts e os chamando de ant:)
#!/bin/sh
pwd='pwd'
osascript -e "tell application \"Terminal\" to do script \"cd $pwd; clear\"" > /dev/null
e
#!/bin/sh
pwd='pwd'
osascript -e "tell application \"Terminal\"" \
-e "tell application \"System Events\" to keystroke \"t\" using {command down}" \
-e "do script \"cd $pwd; clear\" in front window" \
-e "end tell"
> /dev/null