MOTM

I would check the value of the timing capacitor and also of the 
resistors in the timing circuit.  I don't have a schematic in front 
of me (I'm at work) but the timing part of the oscillator is 
probably explained in Paul's explanation of the circuit.  It is easy 
to pick up the wrong capacitor.  You could have done this or Paul 
even could have done this.  Make very sure that the value of the 
timing capacitor matches the schematic and that it is not off by a 
factor of 10.  Then check the resistors around the timing cap.  
Again it is very easy to pick up a resistor that is wrong by a 
factor of 10 (wrong 3rd color band.)  If all else fails, get in 
touch with the master himself.