Minecraft makes me break a block with a tool?

I'm usuing weepcraft and this could possibly be the problem:

When ever I try to break a block it makes me use a tool. I'm on a survival server and the thing is, it makes me use a tool, even if it isn't the correct one. When I was getting seeds it made me use my sword to mine the seeds and I couldn't switch back while getting them. I took the sword out of my inventory and went back to it where my melons that were not visible in my hand-bar-thing came down to it. When i use my hands this happens.
Can someone help? What does Minecraft have against my hands?

Hoikean

Hi you have a server tell me the name so we can play survival me and you and some other people not too many people

Ayo-Gg

If your on someone elses server, they could be using Bukkit, (something for mods, more specificaly plugins) which is making you get a certain item into your inventory. Think of it this way:

The server may be a Adventure Server (AMP) and a plugin could be used, by the server, to give you the correct tool.

If you try and mine Stone, will it switch to a pickaxe? If you mine Wood will it switch to an Axe? If it does, then i'm probably right.

If its your OWN server, then i have no idea… It might be because of the mod but i haven't tried it.

Bob