Description:
------------
In PHP 5.3.1, a putenv() call with a one character value does not assign the value to the variable -- however it does create the variable.

It doesn't matter what type of character it is (alpha, numeric, or other).

A workaround is to add a space character before or after the value, e.g.:

putenv("bar= x");
putenv("bar=x ");

(...as long as this space does not cause problems for the consumers of the variable as it will be part of the string value.)

Reproduce code:
---------------
<?php
putenv("foo=ab");
putenv("bar=c");
var_dump(getenv("foo"));
var_dump(getenv("bar"));
var_dump(getenv("thisvardoesnotexist"));
?>

Expected result:
----------------
We would expect the output to be:

string(2) "ab"
string(1) "c"
bool(false)

which it does under PHP 5.3.0.

Actual result:
--------------
string(2) "ab"
string(0) ""
bool(false)