Doc-view doesn't work properly

[Alan S Barnett]

I'm running emacs 23.2.1 on a linux workstation.
I have doc-view.el installed, and when I type
M-x doc-view
I can specify a file and view it properly.
On the other hand, when I click on a pdf file in dired, the file is 
opened in a new buffer that is in doc-view-mode, but instead of being 
properly displayed I get the contents of the file interpreted as ASCII:

%PDF-1.3
%äãÏÒ
140 0 obj
<<
/Linearized 1.0
/O 142
/H [ 1562 938 ]
/L 1596679
/E 48957
/N 22
/T 1593834
>>
endobj
                                              xref
140 57
0000000015 00000 n
0000001473 00000 n
0000002500 00000 n
0000002769 00000 n
0000002976 00000 n

What should I do to get the document displayed properly when I select it 
from dired?

--
Alan Barnett, PhD
Physicist, NIMH/CBDB
10/3C213
301 402-3507