just got a BSOD

no idea whats up, just received this

Problem signature:
Problem Event Name: BlueScreen
OS Version: 6.1.7600.2.0.0.256.48
Locale ID: 2057

Additional information about the problem:
BCCode: 1a
BCP1: 0000000000041790
BCP2: FFFFFA80016C5390
BCP3: 000000000000FFFF
BCP4: 0000000000000000
OS Version: 6_1_7600
Service Pack: 0_0
Product: 256_1

only thing thats changed since earlier was that BitDefender updated (wasnt just virus defs this time) its strange because its been running for a few hours since l rebooted because of a program update (already mentioned) lm hoping its just a one off however lm somewhat curious as to what caused it as this is the first BSOD lve seen since my win98 days (dont think l ever caused one on winxp)

lve attached the dump file since l thought it was useful.

l found a viewer that allowed me to see the dump file, and from what l see it was caused by a windows file.

Code:

==================================================
Dump File         : 050410-31980-01.dmp
Crash Time        : 04/05/2010 23:57:13
Bug Check String  : MEMORY_MANAGEMENT
Bug Check Code    : 0x0000001a
Parameter 1       : 00000000`00041790
Parameter 2       : fffffa80`016c5390
Parameter 3       : 00000000`0000ffff
Parameter 4       : 00000000`00000000
Caused By Driver  : ntoskrnl.exe
Caused By Address : ntoskrnl.exe+70600
File Description  : NT Kernel & System
Product Name      : Microsoft® Windows® Operating System
Company           : Microsoft Corporation
File Version      : 6.1.7600.16539 (win7_gdr.100226-1909)
Processor         : x64
Computer Name     : 
Full Path         : C:\Windows\Minidump\050410-31980-01.dmp
Processors Count  : 2
Major Version     : 15
Minor Version     : 7600
==================================================