According to the sphinx documentation. The correct build options for compiling libstemmer are --with-libstemmer not --with-stemmer
Additional stemmers provided by Snowball project libstemmer library can be enabled at compile time using --with-libstemmer configure option. Built-in English and Russian stemmers should be faster than their libstemmer counterparts, but can produce slightly different results, because they are based on an older version.
According to the sphinx documentation. The correct build options for compiling libstemmer are --with-libstemmer not --with-stemmer
http://sphinxsearch.com/docs/current.html#installation