Index: src/TortoiseProc/LogDlg.cpp
===================================================================
--- src/TortoiseProc/LogDlg.cpp	(revision 10494)
+++ src/TortoiseProc/LogDlg.cpp	(working copy)
@@ -311,7 +311,7 @@
 		SetWindowText(m_sTitle + _T(" - ") + m_path.GetFilename());
 
 	m_tooltips.Create(this);
-	m_tooltips.AddTool(IDC_SEARCHEDIT, IDS_LOG_FILTER_REGEX_TT);
+	CheckRegexpTooltip();
 
 	SetSplitterRange();
 	
@@ -420,6 +420,20 @@
 	return FALSE;
 }
 
+void CLogDlg::CheckRegexpTooltip()
+{
+	CWnd *pWnd = GetDlgItem(IDC_SEARCHEDIT);
+	// Since tooltip describes regexp features, show it only if regexps are enabled.
+	if (m_bFilterWithRegex)
+	{
+		m_tooltips.AddTool(pWnd, IDS_LOG_FILTER_REGEX_TT);
+		// Anchor may overlap input box, obstructing user's view, so disable it.
+		m_tooltips.ModifyStyles(0, BALLOON_ANCHOR, pWnd);
+	}
+	else
+		m_tooltips.RemoveTool(pWnd);
+}
+
 void CLogDlg::EnableOKButton()
 {
 	if (m_bSelect)
@@ -2176,19 +2190,25 @@
 		temp.LoadString(IDS_LOG_FILTER_REGEX);
 		popup.AppendMenu(MF_STRING | MF_ENABLED | (m_bFilterWithRegex ? MF_CHECKED : MF_UNCHECKED), LOGFILTER_REGEX, temp);
 
-		int oldfilter = m_nSelectedFilter;
-		m_nSelectedFilter = popup.TrackPopupMenu(TPM_RETURNCMD | TPM_LEFTALIGN | TPM_NONOTIFY, point.x, point.y, this, 0);
-		if (m_nSelectedFilter == LOGFILTER_REGEX)
+		m_tooltips.Pop();
+		int selection = popup.TrackPopupMenu(TPM_RETURNCMD | TPM_LEFTALIGN | TPM_NONOTIFY, point.x, point.y, this, 0);
+		if (selection != 0)
 		{
-			m_bFilterWithRegex = !m_bFilterWithRegex;
-			CRegDWORD b = CRegDWORD(_T("Software\\TortoiseSVN\\UseRegexFilter"), TRUE);
-			b = m_bFilterWithRegex;
-			m_nSelectedFilter = oldfilter;
+
+			if (selection == LOGFILTER_REGEX)
+			{
+				m_bFilterWithRegex = !m_bFilterWithRegex;
+				CRegDWORD b = CRegDWORD(_T("Software\\TortoiseSVN\\UseRegexFilter"), TRUE);
+				b = m_bFilterWithRegex;
+				CheckRegexpTooltip();
+			}
+			else
+			{
+				m_nSelectedFilter = selection;
+				SetFilterCueText();
+			}
+			SetTimer(LOGFILTER_TIMER, 1000, NULL);
 		}
-		else if (m_nSelectedFilter == 0)
-			m_nSelectedFilter = oldfilter;
-		SetFilterCueText();
-		SetTimer(LOGFILTER_TIMER, 1000, NULL);
 	}
 	return 0L;
 }
Index: src/TortoiseProc/LogDlg.h
===================================================================
--- src/TortoiseProc/LogDlg.h	(revision 10494)
+++ src/TortoiseProc/LogDlg.h	(working copy)
@@ -149,6 +149,7 @@
 	void UpdateLogInfoLabel();
 	void SaveSplitterPos();
 	bool ValidateRegexp(LPCTSTR regexp_str, rpattern& pat, bool bMatchCase = false);
+	void CheckRegexpTooltip();
 
 
 	virtual LRESULT DefWindowProc(UINT message, WPARAM wParam, LPARAM lParam);
Index: src/Utils/MiscUI/Balloon.h
===================================================================
--- src/Utils/MiscUI/Balloon.h	(revision 10494)
+++ src/Utils/MiscUI/Balloon.h	(working copy)
@@ -505,6 +505,11 @@
 	 */
 	void	RelayEvent(MSG* pMsg);
 	
+	/**
+	 * Hide tooltip immediately.
+	 */
+	void	Pop();
+
 	// Generated message map functions
 protected:
 	void	SetSize(int nSizeIndex, UINT nValue);
@@ -518,7 +523,6 @@
 	void	DisplayToolTip(CPoint * pt, CRect * rect);
 	
 	void	SetNewToolTip(CWnd * pWnd, CPoint * pt = NULL);
-	void	Pop();
 	void	GetMonitorWorkArea(const CPoint& sourcePoint, CRect& monitorRect);
 
 	/**