When I pause Half-Life and access the Steam Overlay, and then exit out of the Steam Overlay, the game resumes but the pause screen is still shown.

Steps to reproduce:

1. Pause Half-Life
2. Launch the Steam Overlay (Shift + Tab)
3. Close out of the Steam Overlay

System Information from Steam:

Processor Information:
    Vendor:  GenuineIntel
    Speed: 2201 Mhz
    8 logical processors
    4 physical processors
    HyperThreading:  Supported
    FCMOV:  Supported
    SSE2:  Supported
    SSE3:  Supported
    SSSE3:  Supported
    SSE4a:  Unsupported
    SSE41:  Supported
    SSE42:  Supported

Network Information:
    Network Speed:  

Operating System Version:
    Ubuntu 12.10 (64 bit)
    Kernel Name:  Linux
    Kernel Version:  3.7.0-7-generic
    X Server vendor:  The X.Org Foundation
    X Server release:  11301901

Video Card:
    Driver:  Intel Open Source Technology Center Mesa DRI Intel(R) Sandybridge Mobile x86/MMX/SSE2

    Driver Version:  3.0 Mesa 9.1-devel
    Desktop Color Depth: 24 bits per pixel
    Monitor Refresh Rate: 59 Hz
    VendorID:  0x10de
    DeviceID:  0xdf6
    Number of Monitors:  1
    Number of Logical Video Cards:  2
    Primary Display Resolution:  1366 x 768
    Desktop Resolution: 1366 x 768
    Primary Display Size: 13.54" x 7.60"  (15.51" diag)
                                            34.4cm x 19.3cm  (39.4cm diag)
    Primary VRAM Not Detected

Sound card:
    Audio device: Intel CougarPoint HDMI

Memory:
    RAM:  7890 Mb

Miscellaneous:
    UI Language:  English
    LANG:  en_US.UTF-8
    Microphone:  Not set
    Total Hard Disk Space Available:  28805 Mb
    Largest Free Hard Disk Block:  5046 Mb

Installed software:

Recent Failure Reports: