Weird problem with blobs/gzipped data

[w0nder]

Hello all
I have following problem, maybe someone can help me?

I store gzipped data in MEDIUMBLOB field (MySQL 4.1.14)
When I retrieve it using adodb I can't unzip it

$query = 'SELECT shorttext from news';
$results = $db->GetAll($query); 
foreach($results AS $result)
   echo gzuncompress($result['shorttext'])."<br />"; 

gzuncompress says that it can't unzip that

when I use standart mysql_query etc everything works ok

Thanks in advance