Blocking SIGCHLD breaks applications using QProcess

kdesudo on hardy cannot successfully run the following short Qt program because it blocks SIGCHLD and QProcess needs that signal:

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#include <QDebug>
#include <QProcess>

int main()
{
    QProcess process;
    process.start("ls");
    qDebug() << "wait for started: " << process.waitForStarted();
    qDebug() << "wait for finished: " << process.waitForFinished();
    return 0;
}
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