"missing port in address" even though I specified a port

[uriklagnes]

Hi, I'm getting this error about missing port even though I am providing port (see 10000 below)

$ docker run --name="logspout" \
        --volume=/var/run/docker.sock:/var/run/docker.sock \
        gliderlabs/logspout \
        'syslog://gray.aggreg.win:10000'      
# logspout v3.2.3 by gliderlabs
# adapters: tls raw syslog tcp udp
# options : persist:/mnt/routes
!! missing port in address gray.aggreg.win

[michaelshobbs]

@uriklagnes try removing the single quotes