"Using SVM with features from external tool"

I wrote some code that generates my feature vectors I want to use for training an SVM.

So far I have been using LibSVM and my feature format is like this:

<class> .=. +1 | -1 | 0
<feature> .=. integer
<value> .=. real
<line> .=. <class> <feature>:<value> <feature>:<value> ... <feature>:<value>

Example:
1 1:0.11764705882352941 2:0.25
1 1:0.11764705882352941 2:0.25

What I want to do is:

Load my feature file
Do some cross validation by generating different models and evaluate on the remaining data and finally create some ROC and Prec/Recall-Charts..

Is that possible? Does RM recognize the format?