Strings in hash tables

[MichaelL@frogware.com]

Surprisingly, this displays "not found":

(let ([h (make-hash-table)])
  (hash-table-put! h "some-key" #t)
  (if (hash-table-get h "some-key" (lambda () #f) )
    (display "found")
    (display "not found")))

This displays "found":

(let ([h (make-hash-table)])
  (hash-table-put! h (string->symbol "some-key") #t)
  (if (hash-table-get h (string->symbol "some-key") (lambda () #f) )
    (display "found")
    (display "not found")))

Two questions:

* Is this the best way to use strings as keys in a hash table?
* Isn't this a strange way for this to work, given expectations about "dictionary" containers?

At the very least, given that this is different from Python, Ruby, TCL, etc., I think it's worth explicity mentioning in the docs how to use strings as hash table keys just to save some annoyance time.