The modem devices ttyACM(x) were removed during the upgrade. OS is retail version. Hwinfo lists the device, and indicates it is attached to ttyACM0. Note the modem is a USB device. Following output is from hwinfo:

61: USB 00.0: 10200 Modem
  [Created at usb.122]
  UDI: /org/freedesktop/Hal/devices/usb_device_22b8_2a22_noserial_if0
  Unique ID: xJ63.N7ciDhSs+JE
  Parent ID: ADDn.5OmDi4+Fw29
  SysFS ID: /devices/pci0000:00/0000:00:1d.0/usb1/1-1/1-1.6/1-1.6:1.0
  SysFS BusID: 1-1.6:1.0
  Hardware Class: modem
  Model: "Motorola PCS Motorola V710"
  Hotplug: USB
  Vendor: usb 0x22b8 "Motorola PCS"
  Device: usb 0x2a22 "Motorola V710"
  Revision: "0.01"
  Device File: /dev/ttyACM0
  Speed: 12 Mbps
  Module Alias: "usb:v22B8p2A22d0001dc02dsc00dp00ic*isc*ip*"
  Config Status: cfg=no, avail=yes, need=no, active=unknown
  Attached to: #64 (Hub)

62: USB 00.1: 0000 Unclassified device
  [Created at usb.122]
  UDI: /org/freedesktop/Hal/devices/usb_device_22b8_2a22_noserial_if1
  Unique ID: OVM7.C80MgsdxZX1
  Parent ID: ADDn.5OmDi4+Fw29
  SysFS ID: /devices/pci0000:00/0000:00:1d.0/usb1/1-1/1-1.6/1-1.6:1.1
  SysFS BusID: 1-1.6:1.1
  Hardware Class: unknown
  Model: "Motorola PCS Motorola V710"
  Hotplug: USB
  Vendor: usb 0x22b8 "Motorola PCS"
  Device: usb 0x2a22 "Motorola V710"
  Revision: "0.01"
  Speed: 12 Mbps
  Module Alias: "usb:v22B8p2A22d0001dc02dsc00dp00ic*isc*ip*"
  Config Status: cfg=no, avail=yes, need=no, active=unknown
  Attached to: #64 (Hub)