problem with rbind

Hi All,

I have a problem with rbind.
I have data that consist of weight height .. etc of 1000 patients. I would
like to find the mean and the standard deviation ( for the weight , height
etc)  for each gender.

data<-read.table("data.txt", header=T, sep='\t')
fdata=NULL

for (i in 1:50){

nn<-names(X)[i]

m<-tapply(X[,i],data$gender,mean,na.rm=T)
s<-tapply(X[,i], data$gender, sd,na.rm=T)

p<-cbind(mean=m,sd.dev=s)

cn<-paste(nn,colnames(p),sep="_")

colnames(p)<-cn

fdata<-rbind(fdata,p)
} 
write.table(fdata, ?results.txt?,sep=?\t?,quote=FALSE, col.names=T)

here is the problem, 
1.	I have a header for each table but only the first one is printed.
2.	the weight_mean is suppose to be on the top of the means but it appears
on the top of the first column ( with no tab before the header)

weight_mean    weight_sd.dev 
F  14.33333  4.932883 
M  34.66667 10.692677 
F  35.00000  7.071068 
M  34.66667 10.692677 
.
.
.

I want the result to look like this with a line separating each table and
each table has a header

       weight_mean    weight_sd.dev 
 F 14.33333  4.932883 
M 34.66667 10.692677 

   hight_mean    hight_sd.dev
F 35.00000  7.071068 
M 34.66667 10.692677 

3.Is there a way to make a title for each table, for example

                    weight
    weight_mean    weight_sd.dev 
 F 14.33333  4.932883 
M 34.66667 10.692677 

I appreciate your help,