TeX's algorithm for hyphenation gives up when it encounters an
\accent command; there are good reasons for this, but it means
that quality typesetting in non-English languages can be difficult.
For TeX macro packages, you can avoiding the effect by using an appropriately encoded font (for example, a Cork-encoded font - see the EC fonts) which contains accented letters as single glyphs. LaTeX users can achieve this end simply by adding the command
to the preamble of their document. Other encodings (notably LY1, once promoted by Y&Y inc) may be used in place of T1. Indeed, most current 8-bit TeX font encodings will “work” with the relevant sets of hyphenation patterns.
With the advance of XeTeX and LuaTeX to the mainstream, a new regime for generating hyphenation tables is in place. For each language, a table is written in Unicode, and “8-bit” versions are generated for use with various LaTeX font encodings. Original sets of patterns remain on CTAN, for use when an older environment is needed.