sudo apt-get install -y usb-modeswitch

cat <> /etc/udev/rules.d/usb_modeswitch.rules
# HUAWEI K3765-HV
SUBSYSTEM=="usb", SYSFS{idVendor}=="12d1", SYSFS{idProduct}=="1520", RUN+="/usr/sbin/usb_modeswitch --default-vendor 0x12d1 --default-product 0x1520 -M 55534243EE0000006000000000000611062000000000000000000000000000"
SUBSYSTEM=="usb", SYSFS{idVendor}=="12d1", SYSFS{idProduct}=="1465", RUN+="/sbin/modprobe -r option"
SUBSYSTEM=="usb", SYSFS{idVendor}=="12d1", SYSFS{idProduct}=="1465", RUN+="/sbin/modprobe usbserial vendor=0x12d1 product=0x1465"
EOF

sudo reload udev

# Links
http://www.linux-community.de/Internal/Artikel/Online-Artikel/Ubuntu-User/2010/02/Mobiler-Koala/%28article_body_offset%29/2