Problems selecting from a MYSQL database

Hello,

connecting to a MYSQL database with SBCL/CLSQL (on both Debian/stable
and Debian/testing) I have some problems:

1. I did not succed with enabling lower case as default, i.e. doing

  (with-gamm-db-connection
    (select [surname] :from [users]))

I get the error:

  While accessing database #<MYSQL-DATABASE ...>
  with expression "SELECT SURNAME FROM USERS":
  Error 1146 / Table 'af20_gamm2010.USERS' doesn't exist
  has occurred.
   [Condition of type SQL-DATABASE-DATA-ERROR]

2. If I work around this by doing

  (with-gamm-db-connection
    (select [|surname|] :from [|users|]))

I obtain the error:
 
  c-string decoding error (:external-format :UTF-8):
  the octet sequence 4 cannot be decoded.
   [Condition of type SB-INT:C-STRING-DECODING-ERROR]

Restarts:
 0: [RETRY] Retry SLIME interactive evaluation request.
 1: [ABORT] Return to SLIME's top level.
 2: [TERMINATE-THREAD] Terminate this thread (#<THREAD "worker" RUNNING {100425BC91}>)

Backtrace:
  0: (SB-INT:C-STRING-DECODING-ERROR :UTF-8 4)
  1: (SB-IMPL::READ-FROM-C-STRING/UTF-8 #.(SB-SYS:INT-SAP #X0094BBF1) CHARACTER)
  2: (UFFI::SBCL-NATURALIZE-CSTRING #<unavailable argument>)[:EXTERNAL]
  3: ((SB-PCL::FAST-METHOD DATABASE-QUERY (T CLSQL-MYSQL:MYSQL-DATABASE T T)) #<unavailable lambda list>)

Can someone help me with this?

Thank you very much.

Nicolas