How to get (non-simple) Unicode characters, e.g, U+1D504?

Hi all,  How would I get the character U+1D504 (Fraktur A) in
LispWorks?  I don't need to be able to view it in the editor or
anything, I just want the object.  The manual says "LispWorks uses
Unicode (UCS-2 encoding) internally in its representation of character
 objects. All Unicode characters can be represented in strings".

My first attempt was to use the #\U+... notation…

CL-USER 25 > #\U+1D504

Error: Wrong character name: U+1D504.
  1 (abort) Return to level 0.
  2 Return to top loop level 0.

But I guess that doesn't have to work, based on the manual:  "I don't
expect the following to work, based on "All simple characters have
names that consist of U+  followed by the code of the character in
hexadecimal, for example #\U+764F  is (code-char #x764F) ."  So then I
tried using code-char, but I don't get a character here either:

CL-USER 27 > (code-char #x1D504)
NIL

What am I missing? U+1D504 certainly falls into the category of "All
Unicode characters", right?  Thanks in advance,  //JT

-- 
Joshua Taylor, http://www.cs.rpi.edu/~tayloj/