Can excessive lava flow cause crash?

[tonibm19]

After some hours my server was not online.
I watched the console, and a line saying "MCServer has crashed" was not there.
And I was inside the MCServer directory.
Then I started the server again, and I saw lava everywhere I've see, someone stupid did it. I will ban him.
But, can excesive lava flow cause server crash?
And lag?

Thank you

EDIT: SOLVED thanks to xoft