Leviathan a Dragon?

Job 40 and 41 introduce the mysterious creatures the behemoth and the leviathan. As the NIV footnote says, most commentators think the behemoth is probably a hippopotamus (or an elephant--although the description of the animal hanging out near the water more strongly suggests a hippo) and the leviathan is a crocodile. And for the most part the descriptions of these creatures seem to fit. But in 41:18-21 it says of the leviathan, "His snorting throws out flashes of light; his eyes are like the rays of dawn. Firebrands stream from his mouth; sparks of fire shoot out. Smoke pours from his nostrils as from a boiling pot over a fire of reeds. His breath sets coals ablaze, and flames dart from his mouth." Most commentators think this is symbolic language describing a crocodile blowing air and water from its mouth and nose in the sunlight. What's interesting is some, however, say there just could have actually existed a dragon-like creature that could produce fire and smoke (The People's Bible). Some of the reasoning:

• While verse 18 is in the form of a simile, the other verses read in a straightforward manner.
• In the Septuagint (Greek translation of the Bible) the word "leviathan" is translated with the word from which the English "dragon" is derived.
• Fire-breathing dragons are described in the ancient folklore of many nations.

I have to say that, with the extent of the wonders of God's creation, I wouldn't say a dragon is impossible, but I would be floored if I ever learned (later in life or in heaven) that fire-breathing creatures existed.