Well, the modern liberal in US page uses the term liberal as we use it, especially for its negative connotations.
But, they are still similar. They are both attuned to liberty, but libertarianism goes a lot further.
[quote]Liberalism refers to a broad array of related ideas and theories of government that advocate individual liberty.[/quote]
[quote]Libertarianism is a political philosophy maintaining that all persons are the absolute owners of their own lives, and should be free to do whatever they wish with their persons or property, provided they allow others the same liberty.[/quote]
In either words, you can be liberal as in pro-liberty (but are more likely to consider yourself a libertarianist), or liberal as more left-wing?