@Oddbloke: It's bundled (and launched) with the USBNetwork hack

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You'll just have to patch the script a tiny bit so that it punches a hole in the firewall for telnet when WiFi is enabled (cf. usbnet/bin/usbnetwork @L255).
Keep in mind that the telnet daemon bundled with USBNetwork is patched to bypass any and all password/user checks, and drops you straight into a root shell. That may not be terribly desirable over WiFi.