BlueZ 5.x is released a while ago (right now 5.13), it brings a lot of important things and bugfixes ( http://code.metager.de/source/xref/linux/bluetooth/bluez/ChangeLog )
Please upgrade for the trusty release
ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: bluez 4.101-0ubuntu10
ProcVersionSignature: Ubuntu 3.12.0-7.15-generic 3.12.4
Uname: Linux 3.12.0-7-generic x86_64
ApportVersion: 2.12.7-0ubuntu3
Architecture: amd64
CurrentDesktop: KDE
Date: Mon Dec 30 05:53:47 2013
InstallationDate: Installed on 2013-12-12 (17 days ago)
InstallationMedia: Kubuntu 13.10 "Saucy Salamander" - Release amd64 (20131016.1)
InterestingModules: rfcomm bnep btusb bluetooth
MachineType: Dell Inc. OptiPlex 760
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.12.0-7-generic root=UUID=5293cdc9-6817-4800-8809-b1d291d3a7e0 ro quiet splash vt.handoff=7
SourcePackage: bluez
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 08/21/2012
dmi.bios.vendor: Dell Inc.
dmi.bios.version: A15
dmi.board.name: 0F373D
dmi.board.vendor: Dell Inc.
dmi.board.version: A00
dmi.chassis.type: 15
dmi.chassis.vendor: Dell Inc.
dmi.modalias: dmi:bvnDellInc.:bvrA15:bd08/21/2012:svnDellInc.:pnOptiPlex760:pvr:rvnDellInc.:rn0F373D:rvrA00:cvnDellInc.:ct15:cvr:
dmi.product.name: OptiPlex 760
dmi.sys.vendor: Dell Inc.
hciconfig:
hci0: Type: BR/EDR Bus: USB
BD Address: 00:0E:A1:00:35:09 ACL MTU: 192:8 SCO MTU: 64:8
UP RUNNING PSCAN
RX bytes:726 acl:0 sco:0 events:27 errors:0
TX bytes:345 acl:0 sco:0 commands:26 errors:0
syslog:
Thank you for taking the time to report this bug and helping to make Ubuntu better. This particular bug has already been reported and is a duplicate of bug 1162781, so it is being marked as such. Please look at the other bug report to see if there is any missing information that you can provide, or to see if there is a workaround for the bug. Additionally, any further discussion regarding the bug should occur in the other report. Feel free to continue to report any other bugs you may find.