No space left on device while there is plenty of space available

Hello all
posting here after scanning the net and tried most of the things offered
still no solution that worked
when I do :

[serverx foo]$ df -h
Filesystem      Size  Used Avail Use% Mounted on
footmpfs        7.9G   60K  7.9G   1% /dev
tmpfs           7.9G     0  7.9G   0% /dev/shm
/dev/da1       99G   38G   61G  39% /

I can see clearly that I have space left
but when I do :

df -i
Filesystem      Inodes   IUsed   IFree IUse% Mounted on
footmpfs       2051811     449 2051362    1% /dev
tmpfs          2054522       1 2054521    1% /dev/shm
/dev/da1       6553600 6553600       0  100% /

I can see the OS inode�s are at 100%

how can i analyze this problem deeper ?and to free the inodes ?
Thanks

There isn't much to analyze. Your root filesystem was configured to allow up to 6,553,600 file to be created on that filesystem and you have 6,553,600 on that filesystem.

You free an i-node by removing all of the hard links to a file.

You haven't told us what filesystem type you are using for your root filesystem. Some filesystem types automatically allocate i-nodes when needed; apparently the filesystem type you're using is not one of those filesystems.

You haven't told us which Linux distribution you're using. Some distributions have administrative utilities to reconfigure the number of i-nodes allocated in some filesystem types. If your distribution doesn't have a utility to do that for the filesystem type you're using and you can't delete a large number of files from your root filesystem; you'll need to make a backup copy of your root filesystem, boot from an alternative device, recreate your root filesystem with more i-nodes configured, restore the files from your backup, and reboot onto your new root filesystem.

Thanks allot for the quick answer
I'm using standard amazon 64 bit Linux on ec2 m3 large vps if this help

On this filesystem display the recent files:

find / -xdev -mtime -30

Then you'll get an idea where to clean up.