Inaccessible/disconnects after certain time period

[GoogleCodeExporter]

What steps will reproduce the problem?
1. Don't access the file system for a while (not sure how long)
2. Try to access the file system through editor or Windows Explorer
3.

What is the expected output? What do you see instead?
It should work normally as it does in the editor or Explorer.
Instead the editor or Explorer hangs and loading icon for mouse doesn't change 
for 30 seconds, then gives error that it's inaccessible.

What version of the product are you using?

win-sshfs: 0.0.1.5 (installed to C:\Program Files (x86)\win-sshfs)
Client OS: Windows 7 Professional 64-bit
Server OS: Linux Debian
Ssh server: SSH-2.0-OpenSSH_5.5p1 Debian-6+squeeze5





Please provide any additional information below.

Original issue reported on code.google.com by [email protected] on 14 Jan 2015 at 9:01