Comment 2 for bug 1407429

usb-modeswitch 2.2.0 and newer versions doesn't work (regression) with lots of 3G modems - I've tested on several devices, like Vodafone (Huawei) K4510 and Huawei E303 - it seems udev or upstart simply doesn't run usb_modeswitch command, because I don't see any activity in /var/log/syslog after installing new usb-modeswitch 2.2.0+repack0-2 from ppa:mariusko/network-manager-backports :(
I see only these lines in /var/log/syslog when using new usb-modeswitch 2.2.0+repack0-2 or newer (also tried 2.2.3 from Ubuntu Wily):
Jul 11 18:26:10 samsung-355V4C udisksd[2513]: Acquired the name org.freedesktop.UDisks2 on the system message bus
Jul 11 18:27:27 samsung-355V4C kernel: [ 151.620238] usb 5-1: new high-speed USB device number 2 using xhci_hcd
Jul 11 18:27:27 samsung-355V4C kernel: [ 151.640910] usb 5-1: New USB device found, idVendor=12d1, idProduct=14c5
Jul 11 18:27:27 samsung-355V4C kernel: [ 151.640926] usb 5-1: New USB device strings: Mfr=3, Product=2, SerialNumber=0
Jul 11 18:27:27 samsung-355V4C kernel: [ 151.640936] usb 5-1: Product: Vodafone Mobile Broadband (Huawei)
Jul 11 18:27:27 samsung-355V4C kernel: [ 151.640944] usb 5-1: Manufacturer: Vodafone Group (Huawei)
Jul 11 18:27:27 samsung-355V4C mtp-probe: checking bus 5, device 2: "/sys/devices/pci0000:00/0000:00:10.0/usb5/5-1"
Jul 11 18:27:27 samsung-355V4C mtp-probe: bus: 5, device: 2 was not an MTP device
Jul 11 18:27:28 samsung-355V4C kernel: [ 151.900199] usb-storage 5-1:1.0: USB Mass Storage device detected
Jul 11 18:27:28 samsung-355V4C kernel: [ 151.905658] scsi5 : usb-storage 5-1:1.0
Jul 11 18:27:28 samsung-355V4C kernel: [ 151.905836] usb-storage 5-1:1.1: USB Mass Storage device detected
Jul 11 18:27:28 samsung-355V4C kernel: [ 151.906209] scsi6 : usb-storage 5-1:1.1
Jul 11 18:27:28 samsung-355V4C kernel: [ 151.906315] usbcore: registered new interface driver usb-storage
Jul 11 18:27:29 samsung-355V4C kernel: [ 152.908139] scsi 5:0:0:0: CD-ROM Vodafone CD ROM (Huawei) 2.31 PQ: 0 ANSI: 2
Jul 11 18:27:29 samsung-355V4C kernel: [ 152.913172] scsi 6:0:0:0: Direct-Access Vodafone Storage (Huawei) 2.31 PQ: 0 ANSI: 2
Jul 11 18:27:29 samsung-355V4C kernel: [ 152.919825] sr1: scsi-1 drive
Jul 11 18:27:29 samsung-355V4C kernel: [ 152.920181] sr 5:0:0:0: Attached scsi CD-ROM sr1
Jul 11 18:27:29 samsung-355V4C kernel: [ 152.920526] sr 5:0:0:0: Attached scsi generic sg3 type 5
Jul 11 18:27:29 samsung-355V4C kernel: [ 152.921044] sd 6:0:0:0: Attached scsi generic sg4 type 0
Jul 11 18:27:29 samsung-355V4C kernel: [ 152.923316] sd 6:0:0:0: [sdc] Attached SCSI removable disk

I tried on USB2 and USB3 ports - same issue on both :(
When downgrade usb-modeswitch (and *-data) to default Trusty packages (usb-modeswitch 2.1.1+repack0-1ubuntu1 and usb-modeswitch-data 20140327-1) these modems works fine.