Colorization and kerning problem with inline lists

Question

The problem is as follows: I need to set an inline list with colored lowercase letters surrounded by black brackets. This is not so hard to achieve, but the problem is that kerning is lost in the process.

If I add two colorization commands: one before the letter and one before the right bracket, then the second command (which restores black color) messes the kerning. Same happens with paralist and enumitem 3 alpha (take a look at "f"; with other fonts the letter and the bracket actually overlap):

\documentclass{book}

\usepackage{paralist}
\usepackage{xcolor}

\setdefaultenum{(a)}{(i)}{A.}{A.}

\begin{document}

\begin{inparaenum}
\item first,
\item second,
\item third,
\item fourth,
\item fifth
\item sixth
\end{inparaenum}

\begin{inparaenum}[(\color{red}a\color{black})]
\item first,
\item second,
\item third,
\item fourth,
\item fifth
\item sixth
\end{inparaenum}

\end{document}

Suggestions?

Answer 1

Color changes put something that inhibits automatic kerning, just like using two different fonts. You can add manually the italic correction (which does something also with upright fonts, if they are well designed)

\begin{inparaenum}[(\textcolor{red}\bgroup a\/\egroup)]

which is also better than reverting to black explicitly.