I have a wierd problem with threading in an ASP.NET application. For some reason, when I run the code in the request thread, everything works as expected. But when I run it in a separate thread, nothing happens.
This is verified by calling the below handler with the three flags "on", "off" and "larma" respectively - in the two first cases everything works, but in the latter nothing happens.

What am I doing wrong here?

In the web project I have a generic handler with the following code:

If task = "on" Then
    Alarm.StartaLarm(personId)
    context.Response.Write("Larmet är PÅ")
ElseIf task = "off" Then
    Alarm.StoppaLarm(personId)
    context.Response.Write("Larmet är AV")
ElseIf task = "larma" Then
    Alarm.Larma(personId)
    context.Response.Write("Larmar... (stängs av automagiskt)")
Else
    context.Response.Write("inget hände - task: " & task)
End If

The Alarm class has the following methods:

Private Shared Sub Larma_Thread(ByVal personId As Integer)
    StartaLarm(personId)
    Thread.Sleep(1000 * 30)
    StoppaLarm(personId)
End Sub

Public Shared Sub StartaLarm(ByVal personId As Integer)
    SandSMS(True, personId)
End Sub

Public Shared Sub StoppaLarm(ByVal personId As Integer)
    SandSMS(False, personId)
End Sub

Public Shared Sub SandSMS(ByVal setOn As Boolean, ByVal personId As Integer)
    ...
End Sub