Description:
------------
The following line lead to a segmenation fault just because I missed the
"/" separator between the resource handler and the $filename variable:

        if (file_exists("ssh2.sftp://{$this->sftp}$filename")) { ... }

The backtrace from the core file starts with:

(gdb) bt
#0  0x00007f53a5643558 in ?? () from /lib/libc.so.6
#1  0x00007f53a2bfd2ce in php_ssh2_fopen_wraper_parse_path (path=0x2764268 "ssh2.sftp://Resource id #659unittest-20121127.txt.gz", 
    type=<value optimized out>, context=0x0, psession=<value optimized out>, presource_id=0x7fff76be3eec, psftp=0x7fff76be3ed8, 
    psftp_rsrcid=0x7fff76be3ee8) at /tmp/pear/temp/ssh2/ssh2_fopen_wrappers.c:226
#2  0x00007f53a2bffc96 in php_ssh2_sftp_urlstat (wrapper=<value optimized out>, url=0x2764268 "ssh2.sftp://Resource id #659unittest-20121127.txt.gz", 
    flags=2, ssb=0x7fff76be3fe0, context=0x4) at /tmp/pear/temp/ssh2/ssh2_sftp.c:390
...


Expected result:
----------------
Error message about invalid resource.

Actual result:
--------------
Segfault