Can't use AT command?

Hi,

I'm trying to run some scripts on my Arduino Yun that heavily rely on the at command. I tried running:
opkg install at

But the package was not found. So I downloaded it from OpenWRT:
https://downloads.openwrt.org/snapshots/trunk/ar71xx/generic/packages/packages/at_3.1.16-2_ar71xx.ipk

Opkg says it installs ok, but I still can't get the at command to work (or even the atd daemon to stay running for that matter). Can anybody help?