How to search for blank cells in SQL

Suppose there are some blank cells  in column [text] of the [table]. How can you find them in SQL2005?
Let's see what are not working.

• SELECT * FROM [table] WHERE [text] IS NULL
• SELECT * FROM [table] WHERE [text] = ''
• SELECT * FROM [table] WHERE LEN([text]) = 0

So what is working.

• SELECT * FROM [table] WHERE LEN([text]) = 1

This essentially implies that LEN() counts the string null terminator as one character. What a broken definition of string length!