Persistant USB device for Sierra wavecom modem

In a (new) file /etc/udev/rules.d/99-usb.rules, I added the following rule:

SUBSYSTEM=="tty", ATTRS{idVendor}=="114f", ATTRS{idProduct}=="1234", ATTRS{serial}=="BH4410035304101", SYMLINK+="wavecom"

The information for this rule:
 udevinfo -a -p $(udevinfo -q path -n /dev/ttyACM0)

De next commands activate the new rule:

 udevcontrol reload_rules
 udevtrigger --verbose

A new symbolic link /dev/wavecom is created and points to the /dev/ttyACM*

[root@klanten-bma rules.d]# ls -l /dev/wavecom
 lrwxrwxrwx 1 root root 7 okt 31 11:47 /dev/wavecom -> ttyACM0
 [root@klanten-bma rules.d]#

In /etc/smsd.conf I changed the device to be:

 device = /dev/wavecom