Problems with replacing into string

I'm trying to execute code like this:

template = "
... here html tags
[sitename]
... here html tags
"

template = template.gsub(/\[sitename\]/,"http://google.com")

But it's not working. What is my mista开发者_高级运维ke?

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Can you describe how it's not working?

In ruby 1.9.2 I get what I expected, the command

puts template

gives

... here html tags
http://google.com
... here html tags