[myTouch 3G, Magic Android Development] wh17m4n:
I was having the same issue with messaging crashing, so I attached logcat, and got the following:

I/ActivityManager( 98): Starting activity: Intent { comp={com.android.mms/com.android.mms.ui.ComposeMessageActivity} (has extras) }

D/dalvikvm( 2674): GC freed 3394 objects / 227896 bytes in 180ms

D/dalvikvm( 98): GC freed 19529 objects / 963928 bytes in 401ms

V/ComposeMessageActivity( 2674): onCreate(): savedInstanceState = null

V/ComposeMessageActivity( 2674): onCreate(): intent = Intent { comp={com.android.mms/com.android.mms.ui.ComposeMessageActivity} (has extras) }

V/ComposeMessageActivity( 2674): onCreate(): mThreadId = 1

V/ComposeMessageActivity( 2674): onCreate(): mMessageUri = null

D/dalvikvm( 2674): +++ active profiler count now 1

I/dalvikvm( 2674): TRACE STARTED: '/sdcard/compose.trace' 8192KB

E/dalvikvm( 2674): Unable to open trace file '/sdcard/compose.trace': Permission denied

D/dalvikvm( 2674): +++ active profiler count now 0

D/AndroidRuntime( 2674): Shutting down VM

W/dalvikvm( 2674): threadid=3: thread exiting with uncaught exception (group=0x40019a68)

E/AndroidRuntime( 2674): Uncaught handler: thread main exiting due to uncaught exception

E/AndroidRuntime( 2674): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.android.mms/com.android.mms.ui.ComposeMessageActivity}: java.lang.RuntimeException: file open failed

E/AndroidRuntime( 2674): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2268)

E/AndroidRuntime( 2674): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2284)

E/AndroidRuntime( 2674): at android.app.ActivityThread.access$1800(ActivityThread.java:112)

E/AndroidRuntime( 2674): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1692)

E/AndroidRuntime( 2674): at android.os.Handler.dispatchMessage(Handler.java:99)

E/AndroidRuntime( 2674): at android.os.Looper.loop(Looper.java:123)

E/AndroidRuntime( 2674): at android.app.ActivityThread.main(ActivityThread.java:3948)

E/AndroidRuntime( 2674): at java.lang.reflect.Method.invokeNative(NativeMethod)

E/AndroidRuntime( 2674): at java.lang.reflect.Method.invoke(Method.java:521)

E/AndroidRuntime( 2674): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:782)

E/AndroidRuntime( 2674): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:540)

E/AndroidRuntime( 2674): at dalvik.system.NativeStart.main(Native Method)

E/AndroidRuntime( 2674): Caused by: java.lang.RuntimeException: file open failed

E/AndroidRuntime( 2674): at dalvik.system.VMDebug.startMethodTracing(Native Method)

E/AndroidRuntime( 2674): at dalvik.system.VMDebug.startMethodTracing(VMDebug.java:155)

E/AndroidRuntime( 2674): at android.os.Debug.startMethodTracing(Debug.java:363)

E/AndroidRuntime( 2674): at android.os.Debug.startMethodTracing(Debug.java:311)

E/AndroidRuntime( 2674): at com.android.mms.ui.ComposeMessageActivity.onCreate(ComposeMessageActivity.java:1682)

E/AndroidRuntime( 2674): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1123)

E/AndroidRuntime( 2674): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2231)

E/AndroidRuntime( 2674): ... 11 more

I/Process ( 98): Sending signal. PID: 2674 SIG: 3

I/dalvikvm( 2674): threadid=7: reacting to signal 3

I/dalvikvm( 2674): Wrote stack trace to '/data/anr/traces.txt'

I/DumpStateReceiver( 98): Added state dump to 1 crashes

Looks like it was trying to open a file on the SD card, but I had the phone plugged into the PC at the time, so it failed, and the exception fell through.

I dont know if that logging it is doing can be disabled, but it does seem like a valid issue.