techblog 

I never used to like dbca for creating a database, I much prefered the more hardcore (and more configurable) method of creating a script to create the database, and indeed all the production databases created here at nominet have been scripted rather than gui’d into existence. However I have found myself using dbca more and more, particularly since we upgraded to Oracle 10.2 a while back, dbca is much more useable, I used to find this java painfully slow, but 10.2 performs much faster. The reason I’ve been using it more is that our developers want empty databases that they then run the auto schema building tools on to give them the schemas to develop against but without data. I find dbca very useful for creating this type of database.
However it seems like dbca (10.2.0.3) has a limit on the size of filesystem that it can understand and throws an error when attempting to install onto a filesystem that is larger than it understands:

There was actually around 16TB of free space available rather than the -1 the gui is suggesting. Thankfully clicking ignore allowed the installation to proceed successfully.