are they 25.4 times too small? We had this trouble when we went to 2006. This is our email to our suplier and their reply...
hope that helps.Blocks are the wrong scale.
I am an experienced AutoCAD user and consider myself more than competent at handling blocks which I have been using for a number of years .However since upgrading to AutoCAD 2006 I find that when I insert a file I have created in an earlier release into my main drawing it is always at the wrong scale.
This problem is related to block insertion units. There are a number system variables that control the scale blocks are inserted into a drawing. INSUNITS controls the scale at which the block is inserted when drawn using different units. If the value of this variable is set to 0 (or undefined in releases where the variable was unavailable) then INSUNITSDEFSOURCE sets the units of an inserted block and INSUNITSDEFTARGET sets the units of the drawing that the block will be inserted into. This is all a bit confusing so the short answer is to set all three to 0 and, assuming that all your blocks are drawn with the same units, no scaling occurs and the blocks appear at the correct size