Welcome to Magento.SE!
I am not having the same issue as you are. It seems to be working for me - so I'm wondering how you're referencing your static block; perhaps you're missing something?
Here's my static block:
And a demo test.php file to output it:
<?php
require('app/Mage.php');
Mage::app();
$block = Mage::app()->getLayout()->createBlock('cms/block')->setBlockId('test');
echo $block->toHtml();
And the output I get:
> php test.php
images/logo.gif
Some things to check:
Make sure you're calling toHtml
on the static block. If so, make sure that the static block is set to use the correct store view (in multistore mode). Make sure that you're using the right block id.