Description of problem:
I can see lot of:

(EE) AIGLX error: dlopen of /usr/lib/dri/nouveau_vieux_dri.so failed (/usr/lib/dri/nouveau_vieux_dri.so: cannot open shared object file: No such file or directory)
(EE) AIGLX: reverting to software rendering

in Xorg.log

Version-Release number of selected component (if applicable):


How reproducible:
100%

Steps to Reproduce:
1.
2.
3.
  
Actual results:


Expected results:


Additional info:
Feel free to close this bug in case it is caused by not supporting DRI for nouveau, which I suppose should not be enabled for nouveau.

01:00.0 VGA compatible controller [0300]: nVidia Corporation NV18GL [Quadro4 380 XGL] [10de:018b] (rev a2) (prog-if 00 [VGA controller])
	Subsystem: nVidia Corporation Device [10de:0169]
	Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
	Status: Cap+ 66MHz+ UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
	Latency: 32 (1250ns min, 250ns max)
	Interrupt: pin A routed to IRQ 16
	Region 0: Memory at de000000 (32-bit, non-prefetchable) [size=16M]
	Region 1: Memory at d0000000 (32-bit, prefetchable) [size=128M]
	Expansion ROM at dfee0000 [disabled] [size=128K]
	Capabilities: [60] Power Management version 2
		Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA PME(D0-,D1-,D2-,D3hot-,D3cold-)
		Status: D0 NoSoftRst- PME-Enable- DSel=0 DScale=0 PME-
	Capabilities: [44] AGP version 3.0
		Status: RQ=32 Iso- ArqSz=0 Cal=3 SBA+ ITACoh- GART64- HTrans- 64bit- FW+ AGP3+ Rate=x4,x8
		Command: RQ=32 ArqSz=0 Cal=0 SBA+ AGP+ GART64- 64bit- FW- Rate=x8
	Kernel driver in use: nouveau
	Kernel modules: nouveau, nvidiafb